Author Correction: Impact of pore anisotropy on the thermal conductivity of porous Si nanowires.

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Impact of pore anisotropy on the thermal conductivity of porous Si nanowires.

Porous materials display enhanced scattering mechanisms that greatly influence their transport properties. Metal-assisted chemical etching (MACE) enables fabrication of porous silicon nanowires starting from a doped Si wafer by using a metal template that catalyzes the etching process. Here, we report on the low thermal conductivity (κ) of individual porous Si nanowires (NWs) prepared from MACE, with values as low as 0.87 W·m-1·K-1 for 90 nm diameter wires with 35-40% porosity. Despite the strong suppression of long mean free path phonons in porous materials, we find a linear correlation of κ with the NW diameter. We ascribe this dependence to the anisotropic porous structure that arises during chemical etching and modifies the phonon percolation pathway in the center and outer regions of the nanowire. The inner microstructure of the NWs is visualized by means of electron tomography. In addition, we have used molecular dynamics simulations to provide guidance for how a porosity gradient influences phonon transport along the axis of the NW. Our findings are important towards the rational design of porous materials with tailored thermal and electronic properties for improved thermoelectric devices.

In-plane thermal conductivity of sub-20 nm thick suspended mono-crystalline Si layers.

We measure the thermal conductivity of a 17.5-nm-thick single crystalline Si layer by using a suspended structure developed from a silicon-on-insulator wafer, in which the Si layer bridges the suspended platforms. The obtained value of 19 Wm(-1) K(-1) at room temperature represents a tenfold reduction with respect to bulk Si. This design paves the way for subsequent lateral nanostructuration of the layer with lithographic techniques, to define different geometries such as Si nanowires, nanostrips or phononic grids. As a proof of concept, nanostrips of 0.5 × 10 µm have been defined by focused ion beam (FIB) in the ultrathin Si layer. After the FIB cutting process with Ga ions at 30 kV and 100 pA, the measured thermal conductivity dramatically decreased to 1.7 Wm(-1) K(-1), indicating that the structure became severely damaged (amorphous). Re-crystallization of the structure was promoted by laser annealing while monitoring the Raman spectra. The thermal conductivity of the layer increased again to a value of 9.5 Wm(-1) K(-1) at room temperature, below that of the single crystalline material due to phonon scattering at the grain boundaries.

Congener profile, occurrence and estimated dietary intake of dioxins and dioxin-like PCBs in foods marketed in the Region of Valencia (Spain).

During 2006-2008, a monitoring program was conducted on 29 target compounds, including PCDD/Fs and dl-PCBs, comprising 150 randomly collected individual food samples marketed in the Region of Valencia, Spain, grouped into 8 categories (vegetables, cereals, fats and oils, eggs, milk and dairy products, fish products, meat and meat products and fish oil). For PCDD/Fs, the highest frequency of detection corresponds to 1,2,3,4,6,7,8-HpCDD, OCDD, 2,3,4,7,8-PeCDF; and PCBs 118, 105 and 156 were the more frequent dl-PCBs. The food groups presenting higher contamination, expressed as toxic equivalents (WHO-TEQs), were fish oil (6.38 pg WHO-TEQ g(-1)fat), fish (1.21 pg WHO-TEQ g(-1)w.w.) and milk and dairy products (0.90 pg WHO-TEQ g(-1)fat). Of all analysed samples, only two fish oils presented levels higher than the EU limits for total WHO-TEQ. The average PCDD/Fs and dl-PCBs intakes were estimated as 2.86 pg WHO-TEQ kg(-1)b.w.d(-1) and 4.58 pg WHO-TEQ kg(-1)b.w.d(-1), for adults and children, respectively, using the deterministic method for chronic exposure. The main contributors to total intake for adults were fish (59%), milk and dairy products (19%), and fat and oils (9%). The average daily intake for adults (2.86 pg WHO-TEQ kg(-1)b.w.d(-1)) is within range of TDI recommended by the WHO (1-4 pg WHO-TEQ kg(-1)b.w.d(-1)), and slightly above the TWI and PTMI adopted by SCF and JECFA respectively.

Beneficios de la determinación del índice tobillo brazo en la consulta de atención primaria / Benefits of determination of the ankle-brachal index in primary health car

Las escalas de riesgo cardiovascular, como el índice de Framingham o el Score, estiman globalmente el riesgo vascular y facilitan una adecuada intervención terapéutica para reducir la morbimortalidad de las enfermedades cardiovasculares; pero en determinadas poblaciones esta estimación puede no ser la adecuada, lo que ha llevado a utilizar pruebas diagnósticas de evaluación directa, capaces de detectar la presencia de lesiones ateroescleróticas en fase asintomática. Una de estas técnicas es la prueba del índice tobillo-brazo (ITB): método diagnóstico fácil, objetivo y no invasivo de la enfermedad arterial periférica (EAP), y probablemente el procedimiento más sencillo de evaluación directa de la lesión arteriosclerótica. Es una prueba barata, precisa y reproducible que no requiere personal especializado, con gran precisión diagnóstica. La diabetes, el tabaco y la edad son los factores que más estrechamente se asocian con un ITB disminuido. La mayor utilidad del ITB reside en su valor como marcador predictor independiente de mortalidad cardiovascular, posibilitando la identificación de pacientes de alto riesgo en prevención primaria. Esta sencilla exploración debe formar parte de la evaluación sistemática del riesgo cardiovascular en las consultas de atención primaria, especialmente en pacientes con diabetes, y así identificar, a los sujetos con mayor riesgo cardiovascular (AU)

Cardiovascular risk scales, such as the Framingham index or Score, estimated overall vascular risk and facilitate appropriate therapeutic intervention for reducing morbidity and mortality of cardiovascular disease in certain populations but this estimate may not be adequate, which has diagnostic tests led to the use of direct assessment, which can detect the presence of atherosclerotic lesions in asymptomatic phase. One such technique is the test of ankle-brachial index (ABI): easy diagnostic method, objective and noninvasive peripheral arterial disease (PAD), and probably the easiest direct assessment of the atherosclerotic lesion. It is an inexpensive, accurate and reproducible that does not require specialized personnel with high diagnostic accuracy. Diabetes, snuff and age are the factors most closely associated with low ABI. The relevance of the ITB lies in its value as a marker independent predictor of cardiovascular mortality, allowing the identification of high risk patients in primary prevention. This simple examination should be part of the systematic evaluation of cardiovascular risk in primary care, especially in patients with diabetes, and identify, subjects with increased cardiovascular risk (AU)

[Disturbances in partners of women suffering from severe postpartum psychiatric disorders]. / Auswirkungen mütterlicher postpartaler Erkrankungen auf das psychische Befinden der Partner.

BACKGROUND: Postpartum psychiatric disorders in women have been discussed more often than postpartum psychiatric disorders in men. However, psychiatric disorders (especially depression) after birth are also experienced by men and may or may not be associated with a postpartum disorder of the mother. The aim of this study is to assess how distressed the partners of women with postpartum psychiatric disorders really are as well as associated factors and the degree of improvement of their emotional well-being after maternal treatment. MATERIALS AND METHODS: For this study, we assessed the psychological distress (SCL-90) in a group of partners of severely ill postpartum depressive and psychotic mothers (N=40), who were inpatients in a Mother-Baby Unit and participated in a longitudinal therapy study. RESULTS: Depression was the only dimension where the partners scored significantly higher than the norm. Between 7.5% and 35% of partners scored above the cut-off point for clinical relevance in the studied dimensions, with the highest figures for hostility (22.5%), interpersonal sensitivity (25%) and depression (35%). Miscarriage, a low severity level of maternal disease and a high level of maternal symptoms were significant predictors for paternal depression. After treatment of the mothers, the levels of symptoms of the partners were reduced. CONCLUSIONS: A postpartum psychiatric disorder of the mother is a risk not only for the baby but also for the father. High levels of awareness for the early detection and early treatment of this condition is essential.

[Children murdered by their mothers in the postpartum period]. / Tötung des eigenen Kindes in der Postpartalzeit.

The parental killing of children constitutes a complex phenomenon which has been reported across numerous cultures and throughout history. Children in the 1st year of life are at the highest risk of filicide. Types of filicide in the postpartum period include altruistic filicide, extended suicide, fatal child maltreatment, and neonaticide. Babies are murdered more frequently by mothers who are psychiatrically disturbed. With high frequency, depressive and psychotic symptoms are related to the newborn or to the maternity itself. The knowledge about maternal factors associated with filicide is not homogeneous. Sociodemographic characteristics are presented in relation to the different types of filicide. Risk constellations that may lead to a child's murder are described.

[Infanticide as a consequence of postpartum bonding disorder]. / Infantizid als Folge einer postpartalen Bindungsstörung.

Parental killing of their own children in the 1st year constitutes a rare phenomenon. Studies on infanticide show that mothers who kill their children are frequently psychiatrically disturbed. Depression is the most common postpartum disorder and may represent a vital danger for both mother and child. The association between depression and infanticide can usually be explained by maternal psychopathologic symptoms. The importance of a mother's bonding to her infant has not often been examined in respect to infanticide. The present case report underlines the importance of postpartum bonding disorder and its relation to a higher risk of infanticide.

[Interactional therapy program for mothers with postpartum mental disorders. First results of a pilot project]. / Interaktionales Therapieprogramm für Mütter mit postpartalen psychischen Störungen. Erste Ergebnisse eines Pilotprojektes.

BACKGROUND: The period around delivery frequently causes psychiatric diseases that may disturb maternal competence and influence bonding behaviour with the child. Until now only a few possibilities have existed for inpatient treatment and therapy for these problems. The therapy program developed in Wiesloch, Germany, is especially well suited to such patients. METHODS: Fifty-three mothers with postpartum disorders (33 depressive, 20 psychotic) were examined before and after therapy. Psychopathologic severity, psychosocial level of functioning, and parameters of the mother-child interaction were assessed and compared. RESULTS: Overall the results showed clear improvements in the assessed parameters at the end of treatment for both psychotic mothers and those with affective disorders. CONCLUSION: The interactional treatment program for postpartum mental disorders leads to a significant reduction in psychic/psychiatric severity and the associated psychosocial impairment and disturbed mother-child interaction. Considerations of the effects of therapy were not possible due to the study design.

Maternal bond and mother-child interaction in severe postpartum psychiatric disorders: is there a link?

Mothers in the puerperium are vulnerable to a wide spectrum of postpartum psychiatric disorders. One of the central psychological processes of the puerperium is the development of an emotional relationship with the baby. The bond to the infant as well as the interaction with the baby are two aspects of the mother-infant relationship that can be disturbed by mothers with postpartum psychiatric disorders. Dysfunctional maternal cognitions may also influence the development of an emotional bonding and the establishment of a positive interaction with the child. The aim of this study is to investigate differences in the self-perceived experience of bonding and the observed mother-child interaction of severely ill postpartum depressive and psychotic mothers. In addition the association between subjective experience of bonding and objective measurement of mother-child interaction will be described. Results show that depressive mothers perceived their bonding to the baby more negatively than psychotic mothers. No differences could be found in the objective interactional behaviour of the mothers in both groups, with the exception that the infants of psychotic mothers showed more eye contact avoidance towards their mothers. The subjective experience of motherhood clearly influences the maternal interactional behaviour with depressive mothers as well as with psychotic mothers.

Bradicardia severa y anestesia espinal en paciente con enfermedad del seno sin diagnosticar / Severe bradycardia and spinal anesthesia in a patient with undiagnosed sinus nodal dysfunction

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Early motherhood and disruptive behaviour in the school-age child.

AIM: To determine the significance of young maternal age, family adversity and maternal behaviour during mother-toddler interaction in the prediction of child disruptive behaviour at age eight. METHODS: From an ongoing longitudinal study of infants at risk for later psychopathology (n = 362), 72 young mothers aged between 15 and 24 y (median 22 y) at first birth were compared with 197 primiparous older mothers ranging in age from 25 to 41 y (median 29 y). Family adversity at childbirth was assessed using a modified version of Rutter's Family Adversity Index (FAI) and measures of child disruptive behaviour at age eight were obtained using Achenbach's Teacher Report Form (TRF). An observational procedure was used to assess maternal behaviour during mother-child interaction at the age of 2 y. RESULTS: Young mothers encountered more adverse family characteristics and were more inadequate, restrictive and more negative during interaction with their toddlers. Their school-aged children showed higher scores on all disruptive behaviour scales of the TRF. Hierarchical regression analyses revealed that family adversity and maternal behaviour during toddler interaction could account for most of the association between early motherhood and child disruptive behaviour. CONCLUSION: The impact of young motherhood on child mental health is not confined to teenage mothers and is mainly attributed to psychosocial and interactional factors.

Insuficiencia hepática secundaria a hepatitis por amoxicilina-ácido clavulánico. Tratamiento con corticoides / Hepatic failure secondary to hepatitis due to amoxicilin-clavulanic acid. Treatment with corticoids

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[Mother-child interaction and externalizing disorders in elementary schoolchildren]. / Mutter-Kind-Interaktion und externalisierende Störungen bei Kindern im Grundschulalter.

OBJECTIVES: The behavior of eight-year-old children with externalizing disorders (ADHD and CD) in interaction with their mothers was examined. METHODS/RESULTS: Mothers of ADHD children were more restrictive and negative towards their children and showed less adequate control than did mothers of normal children. ADHD children paid less attention, were less assertive and helpless, and were more impulsive than controls. CD children were more negative towards their mothers, and were more aggressive and provocative than normal children, while their mothers were more impatient. CONCLUSIONS: An interaction between aggressive child behavior and maternal restrictiveness contributed to increased conduct problems. Hyperactivity was enhanced by the interaction between the impulsive behavior of the child and the aversive maternal response.

Histone acetylation influences thyroid hormone and retinoic acid-mediated gene expression.

Thyroid hormone (T3) and retinoic acid (RA) receptors regulate transcription of the rat growth hormone (GH) gene through binding to a common hormone response element (HRE) in the promoter. We have investigated the effect of histone acetylation on hormone-dependent expression of the rat GH gene. We examined the effect of butyrate, which induces histone hyperacetylation, and trichostatin A (TSA), a highly specific inhibitor of histone deacetylases. GH-mRNA levels were significantly increased in pituitary GH4C1 cells incubated with T3 and RA, and this response was further stimulated in the presence of 1 mM butyrate. The effect of butyrate was mimicked by TSA. Butyrate and TSA also enhanced the activity of recombinant constructs containing the GH promoter directing chloramphenicol acetyl transferase (CAT) reporter gene expression. CAT activity increased by 4- to 8-fold after incubation with 1 nM T3 and 1 microM RA, and this response was stimulated 2- to 4-fold further in the presence of 0.25 mM butyrate. This concentration of butyrate did not influence basal expression of CAT. TSA produced a dose-dependent increase of CAT activity in the absence of ligands, and between 5 and 200 nM potentiated the effect of T3 and RA. These compounds also increased the hormonal response of constructs in which the HRE was linked to heterologous [mouse mammary tumor virus (MMTV) and thymidine kinase (TK)] promoters. With butyrate >1 mM, basal activity of the GH promoter increased by more than 10-fold and the effect of T3 and RA was no longer observed. Overexpression of T3 receptors was able to counteract the stimulation of basal CAT levels caused by butyrate. Thus, in the absence of ligand, the T3 receptor acts as a constitutive repressor of gene expression. Upon binding of the hormone, the T3 receptor is converted into an activator. Our findings suggest that histone acetylation, which alters chromatin structure, may play an important role in hormone-mediated transcriptional regulation.

one-eyed pinhead is required for development of the ventral midline of the zebrafish (Danio rerio) neural tube.

Axial midline structures play a central role as signalling centres during the development of the vertebrate embryo. We have isolated mutant alleles of a new locus, one-eyed pinhead (oep), in the zebrafish that are characterized by cyclopia and impaired development of the floor plate. oep mutants fail to establish expression of axial (zebrafish HNF3beta) and sonic hedgehog in the midline of the neural plate but form a notochord that expresses both genes. In the spinal cord of the 1-day-old embryo, mutation of oep impairs floor-plate but not motor-neuron development. Floor-plate development is absolutely dependent on oep only at early stages, since partial recovery of the floor plate can be detected at 48 h in the spinal cord, suggesting compensatory pathways. Ectopic expression of sonic hedgehog and a dominant-negative protein kinase A regulatory subunit induces expression of floor-plate marker genes in the oep mutant neural tube in a manner indistinguishable from wild-type embryos. Our data suggest that the oep mutation does not impair Sonic hedgehog signalling and thus implicate a second process that acts synergistically with Sonic hedgehog signalling in the specification of the midline of the neuroectoderm and that can partially be compensated for during later development.

Vitamin D interferes with transactivation of the growth hormone gene by thyroid hormone and retinoic acid.

The thyroid hormone, retinoic acid (RA), and vitamin D regulate gene expression by binding to similar receptors which act as ligand-inducible transcription factors. Incubation of pituitary GH4C1 cells with nanomolar concentrations of vitamin D markedly reduces the response of the rat growth hormone mRNA to thyroid hormone triiodothyronine (T3) and RA. The stimulation of growth hormone gene expression by both ligands is mediated by a common hormone response element (TREGH) present in the 5'-flanking region of the gene, and the inhibition caused by vitamin D is due to transcriptional interference of the vitamin D receptor on this DNA element. No inhibition of the basal promoter activity by the vitamin was observed. The response to T3 and RA of a heterologous promoter containing this element, the palindromic T3- and RA-responsive sequence TREPAL, or a direct repeat of the same motif is also inhibited by vitamin D. In contrast, vitamin D strongly induces the activity of constructs containing a vitamin D response element, and neither T3 nor RA reduces vitamin D-mediated transactivation. Transfection with an expression vector for the retinoid X receptor alpha (RXR alpha) increases transactivation by T3 and RA but does not abolish the inhibition caused by the vitamin. Gel retardation experiments show that the vitamin D receptor (VDR) as a heterodimer with RXR weakly binds to the T3- and RA-responsive elements. Additionally, VDR displaces binding of T3 and RA receptors in a dose-dependent manner. Our data suggest the formation of TR-VDR and RAR-VDR heterodimers with RXR. The fact that the same response element mediates opposite effects of at least four different nuclear receptors provides a greater complexity and flexibility of the transcriptional responses to their ligands.