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This Perspective aims at providing a road map to computational heterogeneous photocatalysis highlighting the knowledge needed to boost the design of efficient photocatalysts. A plausible computational framework is suggested focusing on static and dynamic properties of the relevant excited states as well of the involved chemistry for the reactions of interest. This road map calls for explicitly exploring the nature of the charge carriers, the excited-state potential energy surface, and its time evolution. Excited-state descriptors are introduced to locate and characterize the electrons and holes generated upon excitation. Nonadiabatic molecular dynamics simulations are proposed as a convenient tool to describe the time evolution of the photogenerated species and their propagation through the crystalline structure of photoactive material, ultimately providing information about the charge carrier lifetime. Finally, it is claimed that a detailed understanding of the mechanisms of heterogeneously photocatalyzed reactions demands the analysis of the excited-state potential energy surface.

Kinetic rate constants are evaluated computationally for the spin-forbidden thermal relaxations of SCO complexes, unveiling their mechanism, and retrieving accurate TLIESST predictions.

El propósito del presente artículo es revisitar, desde otra perspectiva, la de la maternidad, el papel que dos de las temáticas centrales del Surrealismo, las mujeres y el amor, tuvieron en el movimiento. Para el Surrealismo, la maternidad, necesariamente opuesta al deseo, constituía una barrera para la liberación absoluta de las pasiones a la que confiaban el proyecto revolucionario. Desde el punto de vista femenino, la anulación del sujeto que suponía la maternidad era también la de sus deseos y, por tanto, una limitación para su desarrollo como artistas. Ironizando sobre las fórmulas anteriores y creando otras nuevas, la iconografía surrealista de la maternidad será ante todo la de una deconstrucción: la de la imagen que la presentaba como sinónimo de felicidad femenina., The aim of this article is to revise the role of women and love in surrealism from another perspective: that of motherhood. For the surrealists, motherhood, inevitably opposed to desire, was a barrier to the absolute liberation of the passions, a liberation on which they relied in their revolutionary project. From the feminine point of view, the annulment of the subject that motherhood entailed was also an annulment of her desires and so a limitation for the development of artists. While ironizing on previous iconographies and establishing new formulas, the surrealist iconography of motherhood will be, above all, that of a deconstruction: that of the image presenting the mother as a synonym of female happiness.

MXenes compounds, a recently discovered family of 2D materials, have been found to become semiconductors and photoactive when their pristine surfaces are functionalized with an electronegative termination. MXenes may present...

espanolEl presente articulo pretende estudiar como el gesto de asomarse ha sido sensibilizado en las artes plasticas a partir del Romanticismo, concretamente en su representacion en ventanas o balcones durante las vanguardias historicas. Considerando las ventanas como encuadres de la escision, usando el termino acunado por Argullol, la sensibilizacion de este gesto sera vista como la voluntad de trangredir el espacio asignado como propio, sea este humano o social. Esto es, el intento de superar la ineludible escision que la ventana impone al individuo sera en realidad el intento de acabar con el profundo solipsismo que acecha al ser contemporaneo. EnglishThis article aims to study how the gesture of looking out has been sensitized in the plastic arts since Romanticism, specifically in its representation in windows or balconies during the historical avant-gardes. Considering windows as frames of the excision and using the term coined by Argullol, the awareness of this gesture is seen as the will to transgress their own human or social space assigned. That is, the attempt to overcome the inescapable excision that the window imposes on the individual will actually be the attempt to put an end the profound solipsism that lies in contemporary individuals.

The electron-transfer flavoprotein dehydrogenase gene (ETFDH) encodes the ETF-ubiquinone oxidoreductase (ETF-QO) and has been reported to be the major cause of multiple acyl-CoA dehydrogenase deficiency (MADD). In this study, we present the clinical and molecular diagnostic challenges, at the DNA and RNA levels, involved in establishing the genotype of four MADD patients with novel ETFDH variants: a missense variant, two deep intronic variants and a gross deletion. RNA sequencing allowed the identification of the second causative allele in all studied patients. Simultaneous DNA and RNA investigation can increase the number of MADD patients that can be confirmed following the suggestive data results of an expanded newborn screening program. In clinical practice, accurate identification of pathogenic mutations is fundamental, particularly with regard to diagnostic, prognostic, therapeutic and ethical issues. Our study highlights the importance of RNA studies for a definitive molecular diagnosis of MADD patients, expands the background of ETFDH mutations and will be important in providing an accurate genetic counseling and a prenatal diagnosis for the affected families.

Background The impairment of the hepatic enzyme phenylalanine hydroxylase (PAH) causes elevation of phenylalanine levels in blood and other body fluids resulting in the most common inborn error of amino acid metabolism (phenylketonuria). Persistently high levels of phenylalanine lead to irreversible damage to the nervous system. Therefore, early diagnosis of the affected individuals is important, as it can prevent clinical manifestations of the disease. Methods In this report, the biochemical and genetic findings performed in 223 patients diagnosed through the Portuguese Neonatal Screening Program (PNSP) are presented. Results Overall, the results show that a high overlap exists between different types of variants and phenylalanine levels. Molecular analyses reveal a wide mutational spectrum in our population with a total of 56 previously reported variants, most of them found in compound heterozygosity (74% of the patients). Intragenic polymorphic markers were used to assess the haplotypic structure of mutated chromosomes for the most frequent variants found in homozygosity in our population (p.Ile65Thr, p.Arg158Gln, p.Leu249Phe, p.Arg261Gln, p.Val388Met, and c.1066‐11G>A). Conclusion Our data reveal high heterogeneity at the biochemical and molecular levels and are expected to provide a better understanding of the molecular basis of this disease and to provide clues to elucidate genotype–phenotype correlations., The present study identify and characterize the variants underlying PKU in affected individuals in the Portuguese PKU/HPA cohort. Biochemical data, haplotic analysis and genetic findings performed in 223 patients diagnosed through the Portuguese Neonatal Screening Program (PNSP) is presented. The information obtained will improve the diagnostic applicability of mutational analysis and the capacity to predict the evolution of the disease.

Galanin (Gal) is a neuropeptide with multiple functions that is widely expressed in the central and peripheral nervous systems of vertebrates. Anatomical and functional evidence suggests a possible role in regulating reproduction in fishes. To test this possibility, we have isolated and characterized two gal alternative transcripts in European sea bass (Dicentrarchus labrax) that encode two prepropeptides, respectively of 29 (gal_MT853221) and 53 (gal_MT853222) amino acids. The two gal transcripts are highly expressed in brain, pituitary and gonads, and appear to be differentially regulated in males and females. In males, gal_MT853222 in the hypothalamus and gal_MT853221 in the pituitary were downregulated with the progression of spermatogenesis (stages I-III). Both transcripts are downregulated in testicles of 1-year (precocious) and 2-year spermiating males compared to immature fish of the same age. Gal peptides and receptors are expressed throughout ovarian development in the hypothalamic-pituitary-gonadal (HPG) axis of females. In the testis, immunoreactive Gal-29 and Gal-53 peptides were detected in blood vessels and Leydig cells during the spermatogenesis stages I-III but Gal immunostaining was barely undetected in more advanced stages. In the ovary, both peptides localized in interstitial cells and blood vessels and in theca cells surrounding the maturing oocytes. The immunolocalization of galanin in Leydig and theca cells suggests a possible role in steroid production regulation. The different pattern of gal expression and Gal localization in the testis and ovary may suggest the possibility that androgens and estrogens may also regulate Gal gene transcription and translation. Altogether, this study showed evidence for the possible involvement of locally produced Gal in gametogenesis and that its production is differentially regulated in male and female gonads., This research was funded by the Portuguese national funds from FCT (Foundation of Science and Technology, I.P.) through projects UIDB/04326/2020 and PTDC/MAR-BIO/3890/2012 and by the European Union Seventh Framework Programme AQUAEXCEL (Grant Agreement 262336, TNA project 318). AG and GM were supported by Spanish MINECO (AGL2015-67477-C2-1-R) and CSIC (201640E073). R.S.T.M and P.I.S.P were supported by FCT under contracts of Norma transitória (DL 57/2016/CP1361/CT0021 and DL57/2016/CP6321/CT0015, respectively) with Universidade do Algarve. We acknowledge Zélia Velez for the help during sampling, Deborah Power for IHC advice and Victoria Alvarado and Alicia Felip for providing hypothalamus and pituitary RNA panels.

Glutaric aciduria type 1 (GA-1) is a rare but treatable inherited disease caused by deficiency of glutaryl-CoA dehydrogenase activity due to GCDH gene mutations. In this study, we report 24 symptomatic GA-1 Brazilian patients, and present their clinical, biochemical, and molecular findings. Patients were diagnosed by high levels of glutaric and/or 3-hydroxyglutaric and glutarylcarnitine. Diagnosis was confirmed by genetic analysis. Most patients had the early-onset severe form of the disease and the main features were neurological deterioration, seizures and dystonia, usually following an episode of metabolic decompensation. Despite the early symptomatology, diagnosis took a long time for most patients. We identified 13 variants in the GCDH gene, four of them were novel: c.91 + 5G > A, c.167T > G, c.257C > T, and c.10A > T. The most common mutation was c.1204C > T (p.R402W). Surprisingly, the second most frequent mutation was the new mutation c.91 + 5G > A (IVS1 ds G-A + 5). Our results allowed a complete characterization of the GA-1 Brazilian patients. Besides, they expand the mutational spectrum of GA-1, with the description of four new mutations. This work reinforces the importance of awareness of GA-1 among doctors in order to allow early diagnosis and treatment in countries like Brazil where the disease has not been included in newborn screening programs. info:eu-repo/semantics/publishedVersion

The equivalent core model, or the Z + 1 approximation, has been used to interpret the binding energy, BE, shifts observed in X-ray photoelectron spectroscopy, XPS; in particular to relate these shifts to their origin in the electronic structure of the system. Indeed, a recent paper has claimed that the equivalent core model provides an intuitive chemical view of XPS BE shifts. In the present paper, we present a detailed comparison of the electronic structure provided from rigorous core-hole theory and from the equivalent core model to assess the validity and the utility of the use of the equivalent core model. This comparison shows that the equivalent core model provides a qualitative view of the different properties of initial and core-hole electronic structure. It is also shown that a very serious limitation of the equivalent core model is that it fails to distinguish between initial and final state contributions to the shifts of BEs which seriously reduces the utility of the information obtained with the equivalent core model. Indeed, there is a danger of making an incorrect assignment of the importance of relaxation because the equivalent core model appears to stress the role of final state effects. Given the importance of the distinction of initial and final state effects, we provide rigorous definitions of these two effects and we discuss an example where an incorrect interpretation was made based on the use of the equivalent core model.

The Portuguese Newborn Screening Program is a public health program that started in 1979, screening for PKU, being totally supported by public funds. It's a non-mandatory well implemented program that testes about 99.9% of Portuguese newborns. In the actual screening panel encompasses 26 disorders, including inborn errors of metabolism, congenital hypothyroidism and cystic fibrosis. Sample collection is advised to be made at 3rd day of life and treatment begins in average by the 10th day. Every testes are performed in one single national laboratory, that processes about 88,000 samples/year. In the 41 years of program existence, more than 3,800,000 newborns were screened and 2,130 affected newborns detected, reflecting the positive impact of the Program in the population. Future perspectives include the increase of program value in terms of public health by optimizing the screening of the disorders already screened and evaluation the possibility of adding others.El Programa Portugués de Cribado Neonatal es un programa de Salud Pública a nivel nacional, que tuvo su inicio en 1979 con el cribado de la fenilcetonuria y es financiado totalmente por el Estado portugués. Se trata de un programa no obligatorio, con una tasa de cobertura del 99,8%, en el que hoy en día se criban veintiséis enfermedades, incluyendo metabolopatías, hipotiroidismo congénito y fibrosis quística. La toma de muestra se hace al 3er día de vida y el tratamiento de los neonatos afectos empieza en torno al 10º día. Todos los análisis están centralizados en un único laboratorio, que procesa aproximadamente 88.000 muestras al año. En los últimos cuarenta y un años se cribaron más de 3.800.000 neonatos y se detectaron 2.130 niños afectados, lo que es un indicador del impacto del programa en la población. Los desafíos futuros incluyen la búsqueda de nuevas estrategias para incrementar el valor del programa, donde se evalúen nuevas enfermedades a cribar y la optimización del cribado actual.

The influence of electron correlation into the decomposition of core level binding energy shifts, measured by X-ray photoelectron spectroscopy (XPS), into initial and final effects is analysed for a series of molecules where these effects are noticeable. Moreover, the series of molecules is chosen in such a way that electron delocalization and increasing number of electrons may provide a large screening of the core hole. A detailed analysis shows that the Hartree-Fock decomposition is biased whereas a physically meaningful decomposition is obtained when electron correlation effects are taken into account. The results show that in this case, trends in core level binding energy shifts are driven by initial state effects thus providing further support to the use of these observable quantities to interpret changes in the chemical bond in the neutral molecule rather than on the core ionized cation. Consequences for the theoretical interpretation of XPS data in materials and surface science are discussed.

The non-specific immunity can induce iron deprivation as a defense mechanism against potential bacterial pathogens, but little information is available as to its role in Antarctic fish. In this study the response of iron metabolism related genes was evaluated in liver and head kidney of the Antarctic notothenoids Notothenia coriiceps and Notothenia rossii 7 days after lipopolysaccharide (LPS) injection. Average plasma Fe2+ concentration was unaffected by treatment in any of the species. The gene expression response to LPS varied between tissues and species, being stronger in N. coriiceps and more prominent in the head kidney than liver. The reaction to LPS was marked by increased individual variability in most genes analyzed, even when the change in expression was not statistically significant, suggesting different individual sensitivity and coping responses in these wild fish. We found that iron related genes had an attenuated and homogenous response to LPS but there was no detectable relationship between plasma Fe2+ and gene expression. However, overall in both tissues and species LPS exposure set a multilevel response that concur to promote intracellular accumulation of iron, an indication that Antarctic Notothenoids use innate nutritional immunity as a resistance mechanism against pathogens. FCT-NSFC/0002/2016; CCMAR/Multi/04326/2013; PTDC/BIAANM/3484/2014 info:eu-repo/semantics/publishedVersion

The O(1s) and C(1s) XPS core-level binding energies. BEs, have been studied as a function of the C–O internuclear distance for a large range of distances. The BE(r) for both BEs show considerable variation over the distances studied which is, however, different for the O(1s) and C(1s) BEs. The origin of the dependence on C–O distance is established and shown to involve more than the electric field generated because of the charge separation within CO being C+q and O−q . Furthermore, the BE(r) is shown to be different for Hartree–Fock and correlated wavefunctions indicating that the BE(r) can provide evidence of how electron correlation modifies the valence charge distribution. The difference between the O(1s) and C(1s) BEs is examined and it is proposed that this difference can be used as a measure of the accuracy of theoretically predicted BEs. It is believed that the features found for CO may be representative for the BE variations with geometry for other systems; an effect that has been mostly overlooked.

Investigation of the excited state decay dynamics of transition metal systems is a crucial step for the development of photoswitchable molecular based ma- terials with applications in growing fields as energy conversion, data storage or molecular devices. The photophysics of these systems is an entangled problem arising from the interplay of electronic and geometrical rearrangements that take place on a short time scale. Several factors play a role in the process: various electronic states of di↵erent spin and chemical character are involved, the system undergoes important structural variations and several nonradiative processes can occur. Computational chemistry is a useful tool to get insight into the micro- scopic description of the photophysics of these materials since it provides unique information about the character of the electronic spin states involved, the ener- getics and time evolution of the system. In this review article, we present an overview of the state of the art methodologies available to address the several aspects that have to be incorporated to properly describe the deactivation of excited states in transition metal complexes. The most recent developments in theoretical methods are discussed and illustrated with examples.

The deactivation pathway of the light-induced spin crossover process in two Fe(II) complexes has been studied by combining density functional theory calculations for the geometries and the normal vibrational modes and highly correlated wave function methods for the energies and spin orbit coupling effects. For the two systems considered, the mechanism of the photoinduced conversion from the low-spin singlet to the high-spin quintet state implies two intersystem crossings through intermediate triplet states. However, for the [Fe(mtz)(6)](2+) complex, the process occurs within few picoseconds and involves uniquely metal-centered electronic states, whereas for the [Fe(phen)(3)](2+) system the deactivation channel involves both metal to ligand charge transfer and metal-centered states and takes place in a femtosecond time scale.

X-ray Photoelectron Spectroscopy (XPS) applied to N-doped graphene leads to a rather broad N(1s) core level signal that, based on different sources available in the literature, is most often interpreted by fitting the experimental spectra to three peaks. The resulting N(1s) features are assigned to graphitic, pyrrolic, and pyridinic nitrogen, even if these are far from being uniquely defined in the literature. This broadly accepted interpretation has been questioned by recent accurate Hartree-Fock calculations concluding that graphitic and pyrrolic N(1s) core level binding energies are too close to be distinguished. Consideration of models with N in other so far unexplored environments such as N dimers or N at defects show some variations in the calculated core level binding energies. However, these are not large enough to justify a third peak and suggest that the usual three peaks interpretation of the N(1s) XPS in N-doped graphene may be an artefact caused by the fitting procedure. New measurements have been carried out for samples of N-doped graphene and the obtained N(1s) spectra fitted to two or three peaks. It turns out that the spectra can be equally fitted using two or three peaks but only the former is consistent with the results of the unbiased ab initio calculations which calls for a revision of the usual assignment.

The ability of density functional theory (DFT) based methods to predict the multiplet splitting arising from the core hole ionization of molecules such as NO and O2, exhibiting an open shell grounds state, is explored. In the NO molecule, N(1s) or O(1s) ionization leads to 3Π and 1Π multiplets whereas for O2, the presence of an O(1s) core hole leads to doublet and quartet multiplets with distinct BEs. Multiplet splittings obtained using different exchange-correlation functionals show an overall good agreement with experiment and minor variations within the functionals studied when spin contamination resulting from unrestricted DFT calculations is accounted for.

In this paper, the contribution of many body effects to the X-ray photoelectron spectroscopy, XPS, of an NO molecule are studied using wavefunction theory where the specific consequences of different many-body terms are examined and contrasted. It is shown that there is a differential importance of the many-body effects for the different configurations involved in the XPS. These are the ground, initial state configuration and final, N(1s) and O(1s) core-hole ionic configurations. The consequences of the many-body effects are examined for the binding energies, BEs, to the two final state multiplets, triplet and singlet, for each of the core ions and for the relative intensities of the XPS transitions to these multiplets. The many body effects examined are those described as static effects that arise for individual terms that are important. The objective is to understand the chemical and physical origins that determine the importance of the correlation effects for the XPS, rather than to obtain very accurate predictions of the BEs. An important theoretical construct that is tested and justified is the equivalent core approximation where the core ionized atom is replaced by the next higher element in the periodic table. This construct allows us to establish a correlation for the relative importance of the many-body effects in terms of effective charges of the different atoms. This is a correlation that has not been considered before and that we expect may have general relevance. The potential of the effects that we have identified for the XPS of NO to be relevant for the XPS of more complex, condensed phase systems is considered.

Investigation of the excited state decay dynamics of transition metal systems is a crucial step for the development of photoswitchable molecular based ma- terials with applications in growing fields as energy conversion, data storage or molecular devices. The photophysics of these systems is an entangled problem arising from the interplay of electronic and geometrical rearrangements that take place on a short time scale. Several factors play a role in the process: various electronic states of di↵erent spin and chemical character are involved, the system undergoes important structural variations and several nonradiative processes can occur. Computational chemistry is a useful tool to get insight into the micro- scopic description of the photophysics of these materials since it provides unique information about the character of the electronic spin states involved, the ener- getics and time evolution of the system. In this review article, we present an overview of the state of the art methodologies available to address the several aspects that have to be incorporated to properly describe the deactivation of excited states in transition metal complexes. The most recent developments in theoretical methods are discussed and illustrated with examples.

Core level binding energies, directly measured by X-ray photoelectron spectroscopy (XPS), provide unique information regarding the chemical environment of atoms in a given system. However, interpretation of XPS in extended systems may not be straightforward and requires assistance from theory. The different state-of-the-art theoretical methods commonly used to approach core level binding energies and their shifts with respect to a given reference are reviewed and critically assessed with special emphasis on recently developed theoretical methods and with a focus on future applications in materials and surface sciences.

Spin-orbit couplings have been calculated in twenty snapshots of a molecular dynamics trajectory of [Fe(bpy)

Spin-orbit couplings have been calculated in twenty snapshots of a molecular dynamics trajectory of [Fe(bpy)3]2+ to address the importance of geometrical distortions and second-order spin-orbit coupling on the intersystem crossing rate constants in the light-induced spin crossover process. It was found that the effective spin-orbit coupling between the 3MLCT and 5T2 state is much larger than the direct coupling in the symmetric structure, which opens the possibility of a direct 3MLCT-5T2 deactivation without the intervention of triplet metal-centered states. Based on the calculated deactivation times, we conclude that both the direct path- way and the one involving intermediate triplet states are active in the ultrafast population of the metastable HS state, bringing in agreement two experimental observations that advocate for either deactivation mechanism. This resolves a long-standing dispute about the deactivation mechanism of Fe(II)-polypyridyl complexes in particular, and about light-induced magnetism in transition metal complexes in general.

The deactivation pathway of the light-induced spin crossover process in two Fe(II) complexes has been studied by combining density functional theory calculations for the geometries and the normal vibrational modes and highly correlated wave function methods for the energies and spin-orbit coupling effects. For the two systems considered, the mechanism of the photoinduced conversion from the low-spin singlet to the high-spin quintet state implies two intersystem crossings through intermediate triplet states. However, for the [Fe(mtz)

The neuropeptide galanin (Gal) is a putative factor regulating puberty onset and reproduction through its actions on the pituitary. The present study investigated the pituitary responsiveness to galanin and the patterns of galanin receptors (Galrs) expression throughout the reproductive cycle of two years old male European sea bass (Dicentrarchus labrax), an important aquaculture species. Quantitative analysis of pituitary and hypothalamus transcript expression of four galr subtypes revealed differential regulation according to the testicular developmental stage, with an overall decrease in expression from the immature stage to the mid-recrudescence stage. Incubation of pituitary cells with mammalian 1–29 Gal peptide induced significant changes in cAMP concentration, with sensitivities that varied according to the testicular development stages. Furthermore 1–29 Gal was able to stimulate both follicle stimulating hormone (Fsh) and luteinizing hormone (Lh) release from pituitary cell suspensions. The magnitude of the effects and effective concentrations varied according to reproductive stage, with generalized induction of Fsh and Lh release in animals sampled in January (full spermiation). The differential expression of galrs in pituitary and hypothalamus across the reproductive season, together with the differential effects of Gal on gonadotropins release in vitro strongly suggests the involvement of the galaninergic system in the regulation the hypothalamus-pituitary-gonad axis of male sea bass. This is to our knowledge the first clear evidence for the involvement of galanin in the regulation of reproduction in non-mammalian vertebrates., This work was supported by the Portuguese Foundation for Science and Technology [grant numbers SFRH/BPD/84033/2012, PTDC/MAR-BIO/3890/2012, UID/Multi/04326/2013]; the European Union Seventh Framework Programme [AQUAEXCEL grant number 262336]; the Spanish Ministry of Science and Innovation (MICINN) and the Spanish Ministry of the Economy and Competitiveness (MINECO) [KISSCONTROL project, AGL2009-11086]; the Spanish Ministry of the Economy and Competitiveness and the Regional Government of Valencia (REPROBASS project, PROMETEOII/2014/051).

We use a total energy difference approach to explore the ability of various density functional theory based methods in accounting for the differential effect of static electron correlation on the C(1s) and O(1s) core level binding energies (BEs) of the CO molecule. In particular, we focus on the magnitude of the errors of the computed C(1s) and O(1s) BEs and on their relative difference as compared to experiment and to previous results from explicitly correlated wave functions. Results show that the different exchange-correlation functionals studied here behave rather erratically and a considerable number of them lead to large errors in the BEs and/or the BE shifts. Nevertheless, the TPSS functional, its TPSSm and RevTPSS derivations, and its corresponding hybrid counterpart, TPSSh, perform better than average and provide BEs and BE shifts in good agreement with experiment.

Objective Birth prevalence of Cobalamin (Cbl) C or D defects in Portugal is an estimated 1:85,000, one of the highest worldwide. We compared the genotype/phenotype of patients identified with CblC or CblD before and after the implementation of expanded newborn screening. Methods Twenty-five Portuguese CblC/D patients, 14 symptomatic and 11 identified through screening, were diagnosed using gas chromatography or tandem mass spectrometry. Molecular characterization was performed through the study of MMACHC and MMADHC genes. Results The most common MMACHC mutation, c.271dupA, was present in 100% of MMACHC alleles of all CblC screened patients, in contrast with the 61% identified before expanded newborn screening. All studied cases (except one, who presented a CblD deficiency) presented a CblC defect. More CblC late-onset patients were diagnosed before the introduction of newborn screening than in the post newborn screening era, probably because some early onset patients died without a definitive diagnosis. Conclusion The molecular data found in this cohort contribute to the improvement of screening and diagnosis of Cbl defects and would enable a confirmatory diagnosis of these patients, reducing the need for complex, costly, laborious, and time-consuming biochemical/enzymatic tests.

10.1039/c3dt52027g The spin crossover behavior of the two [Fe(mtz)6](2+) complexes occupying different lattice sites in Fe(mtz)6(BF4)2 is addressed by combining quantum chemical calculations with a careful analysis of the crystal structure. It is first established from the calculations that the energy difference between high spin and low spin states depends on the orientation of the tetrazole ligands; small rotation angles favor the low spin state, while for angles larger than ~20° the high spin state is more stable. The crystal structure shows that the two complexes have different average rotation angles of the ligands. It is larger for the site that remains HS down to low temperatures and smaller for the site that shows spin crossover to LS. The origin of the different rotation angles is found to be determined by a subtle interplay amongst steric repulsion between the ligands, HF interactions between the complex and the counterions, and intersite interactions involving NH contacts and p-p interactions between the N[double bond, length as m-dash]N double bonds of the tetrazole rings.

The deficiency of 3-methycrotonyl-CoA carboxylase (3-MCC; EC 6.4.1.4) is an autosomal recessive organic aciduria that is included in the newborn screening programs of several countries. This study reports data mainly obtained from the Portuguese newborn screening program collected over a ten-year period. Analysis of the MCCC1 and MCCC2 genes yielded 26 previously unreported mutations and a variant of clinically unknown significance. These mutations are discussed in the context of their likely impact on the function of the 3-MCC enzyme, with a view to exploring whether a phenotype-genotype correlation might be discerned. Further, these mutations were analysed in the context of what is known of the MCCC1 and MCCC2 mutational spectra, information that will be useful in both clinical and laboratory practice.

The light-induced spin crossover in FeII complexes is studied with complete active space second-order perturbation theory. The potential energy surfaces of the low-spin and high-spin states are determined as function of the Fe--ligand distance interpolating between the high-spin and low-spin equilibrium geometries. In addition, we calculate the relative energies of the lowest excited states along this coordinate. To address the mechanism of spin crossover, the metal-to-ligand charge transfer states with singlet, triplet, and quintet spin coupling were also treated. The curves of the singlet and triplet MLCT states nearly coincide, but the quintet MLCT curve is higher in energy and the equilibrium distance displaced to larger distances. The possible deactivation mechanisms of the 1MLCT state are discussed considering the relative energies and spin-orbit coupling matrix elements of the relevant electronic states. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 111:3385–3393, 2011

INTRODUCTION: The Portuguese Neonatal Screening Programme (PNSP) was started in 1979 for phenylketonuria (2,590,700 newborns screened; prevalence 1:11,031) and, shortly after, for congenital hypothyroidism (2,558,455 newborns screened; prevalence 1:3,174). In 2004, expanded neonatal screening was implemented in the National Laboratory. The programme is not mandatory and has 99.8% coverage of the country (including Madeira and the Azores islands). MATERIAL AND METHODS: In the past 4 years, 316,243 neonates were screened with the use of tandem mass spectrometry (MS/MS) to test for selected amino acids and acylcarnitines. RESULTS: During this time, 132 patients were identified with 24 different inherited metabolic diseases (classic forms and variants). To date, the global frequency for all disorders integrated into the PNSP is estimated to be 1:1,380, with 1:2,396 for metabolic disorders. A total of 379 tests (0.12%) were classified as having false positive results, yielding an overall specificity of 99.9%. Despite the low frequency of several disorders, the positive predictive value of the overall MS/MS screening was found to be 26%, reflecting high diagnostic specificity of the method. Diagnostic sensitivity of extended screening for the different groups of disorders was 100%. Eight cases of maternal disorders [three glutaric aciduria type I, one carnitine transporter defect, and four 3-methylcrotonyl coenzyme A (CoA) carboxylase deficiency] were also detected through newborn screening. CONCLUSIONS: Our data support the advantage of a centralised laboratory for screening an elevated number of samples and making decisions if relying on a clinical network able to provide fast treatment and a good outcome in the screened cases.

A systematic density functional study of the adsorption and dissociation of O2 on the (001) surface of several transition metal carbides (TCMs; TM = Ti, Zr, Hf, V, Nb, Ta, Mo) is presented. It is found that O2 may adsorb molecularly on two different sites with similar adsorption energy. At these sites, either O2 bridges two surface metal (M) atoms or it is placed directly on top of a M surface atom. A case apart is δ-MoC, where O2 adsorption on top of surface Mo atoms is far up in energy with respect to bridging two surface Mo atoms. The relative stability of O2 on these TMCs is dominated by the electron back-donation between the surface and O2 and the stabilization of the resulting partially charged molecule by the surface metal sites. Three reaction paths leading to O2 dissociation have been considered. The first reaction pathway starts from M−M bridge molecular adsorption and lead to O atoms on top of surface M atoms (TSM) and the second one (TSC) starts from on top molecular adsorption and lead to fin...

The optical transition energies of a point defect in MgO(100), consisting of an oxygen vacancy with one trapped electron and an OH − group adsorbed nearby the surface oxygen vacancy (the F s + (OH − ) center), have been studied by means of ab initio multiconfiguration second order perturbation theory (CASPT2) and Density Functional (DFT) calculations on embedded cluster models. We find that a method that takes explicitly into account electronic correlation effects is required to properly predict the first transition energies. The lowest transition energy of the F s + (OH − ) center on a terrace site is very similar to the one reported in previous studies of F + centers on a regular MgO(100) surface (F s + center). Experiments have difficulty distinguishing between these two kinds of point defects based solely on the optical spectra. We have also considered the situation where the vacancy is located at low-coordinated sites like steps and corners. The results show that the loss of coordination decreases the transition energies in agreement with what has been reported in previous studies for “classical” F s + centers.

In the present paper, a density functional systematic study of the adsorption of atomic oxygen on the (001) surface of several transition-metal carbides (TMC, TM = Ti, Zr, Hf, V, Nb, Ta, Mo) is reported. Our calculations using both PW91 and RPBE exchange correlation functionals show that on group 4, TMC (100) oxygen atoms highly prefer the hollow sites surrounded by one carbon atom and two metal atoms (MMC). On the rest of TMC of group 5 and 6, a competition between this site and the adsorption on top of a metal atom (M-top) is observed. A third possible competitive site is found for the δ-MoC site, where a kind of CO-like molecule is formed and adsorbed on the carbon vacancy site. The strong interaction of O with the C explains the availability of carbon removal from the TMC and the formation of metal oxocarbide compounds by oxidation, especially at high temperatures. An electronic analysis is also included to understand the different behaviors of the carbides toward O adsorption.

A systematic density functional study of NO dissociation on Rh(111), Cu(111), and two different RhCu(111) bimetallic surfaces was conducted using a periodic supercell approach. Properties of the transition states, energy barriers, and transition state theory reaction rates were obtained for relevant situations involving NO adsorbed on different compositions of fcc and hcp sites. The results demonstrate that the superior activity of Rh versus Cu toward NO dissociation has its origin in the stronger adsorption on the former surface, which permits NO dissociation without the need for extra energy to the system. Moreover, the presence of Cu atoms on a Rh surface exerts a promoter effect by decreasing the energy barrier with respect to the value for the single crystal surface. In contrast, the presence of Rh atoms on a Cu surface has a poisoning effect. Analysis of the adsorption energies provides some important clues as to the modification of the corresponding energy barriers induced by the presence of the second metal. The results indicate that it is possible to improve the catalytic properties of Rh surfaces by adding small quantities of Cu, in agreement with previous experimental findings.

The effect of spin-orbit coupling is assessed through the spin-orbit state interaction method. This method involves a two-step procedure to include both dynamical electron correlation effects and spin-orbit effects on the relative energies of the low-lying electronic states. Accurate energies of the spin free states are obtained with the complete active space self-consistent field/complete active space second-order perturbation theory (CASSCF/CASPT2) procedure. Second, the spin-orbit coupling is taken into account by interaction of the CASSCF states using the CASPT2 relative energies. The method is validated on the Co2+ ion in vacuum and in the ionic insulator CoO. Afterward the method is applied to CoCl2(PPh3)2 and the dinuclear complexes [TM2Cl6]2− (TM = Mn, Fe, Co). For the monomeric species, the results compare favorable with experimental data or fully relativistic benchmarks. We discuss the difficulties to interpret the dimer results in terms of the parameters that are usually derived from experiment. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006

We recently developed a scheme for first-principles calculations of hopping matrix elements between localized states in extended systems. We apply the scheme to the determination of double exchange (DE) parameters in lightly hole-doped LaMnO(3) and electron-doped CaMnO(3). DE is one of the important factors for understanding the properties of doped manganites. The calculations are based on the construction of wave functions for localized hole states or localized electron states for large embedded clusters. The wave functions of these clusters are expressed in terms of localized orbitals, obtained from calculations on smaller units, or "fragments," centered around a transition metal ion. The starting point of electronic states expressed in terms of localized orbital sets is conceptually attractive. It also allows for a rigorous treatment of local electron correlation and electronic relaxation effects. In the present study, the fragments are embedded [MnO(6)] units. The large clusters contain either two or four Mn ions and all neighboring oxygen ligands. The results are compared with conventional embedded cluster calculations. In both compounds, the effective hopping matrix elements, or "double exchange" (DE) parameters, in the ab planes (in the Pbnm space group) are larger than along the c axes. We found nearly perfect agreement with the Anderson-Hasegawa model for the spin dependence of the DE parameters. Nearest-neighbor parameters are more than one order of magnitude larger than next nearest-neighbor parameters. In LaMnO(3) the DE in the ab planes is approximate to -0.26 eV. If there were no Jahn-Teller distortion present in the material, it would have been twice as large. In CaMnO(3), the corresponding nearest-neighbor DE parameter for hopping of a doped electron in the ab planes is only approximate to -0.17 eV, due to the antiparallel spin coupling. However, since this interaction is much larger than the exchange coupling, we suggest that it induces local ferromagnetic clusters around the doped electrons. (C) 2006 Wiley Periodicals, Inc.

The interaction of Cl on different metal surfaces has been studied by density functional theory. The surface is represented by periodic slab models. It is shown that the change on the surface work function induced by the presence of the adsorbed halide can be either positive or negative, depending on the surface metal. While this has already been pointed out for some particular cases such as Cl on Cu(0 0 1) or N on W(1 0 0), we show that this effect may also appear in the case of having the same adsorbate on different metal surfaces. Therefore, one may conclude that the use of the work function change to extract information about the net charge on the adsorbate should be regarded with extreme caution.

The low to high spin energy transition of Ni adsorbed on regular and defective sites of MgO(100) and the relative strengths of bulk and surface magnetic coupling constants of first row transition metal oxides (MnO, FeO, CoO, NiO and CuO) are taken as examples to illustrate some deficiencies of density functional theory (DFT). For these ionic systems a cluster/periodic comparison within the same computational method (either DFT or Hartree-Fock) is used to establish that embedded cluster models provide an adequate representation. The cluster model approach is then used to obtain accurate values for the magnetic properties of interest by using explicitly correlated wavefunction methods which handle the electronic open shell rigorously as spin eigenfunctions.

Cluster models and hybrid density functional theory calculations are used to study the effect of an external electric field on the properties and bonding mechanism of CO on various RhCu bimetallic surfaces. The presence of an external electric field induces changes in the geometry and vibrational frequency of the chemisorbed molecule. Several methods of analysis establish that the electric field effects are not just of electrostatic nature but do affect the bonding mechanisms as well. In any case, the electric field effects observed for various RhCu bimetallic surfaces are not at all different from what is known for monometallic surfaces. The present study permits to conclude that the effect of an external electric field on the properties of CO adsorbed on bimetallic RhCu surfaces of different composition follows the same trend exhibited by the single metal surfaces.