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OBJECTIVE: This study examines whether parental emotional distress during the first pandemic-related school shutdown in 2020 in Germany affected the development of primary school students' mathematical skills and investigates changes in parents' working conditions as triggers of cascading stress processes. BACKGROUND: The Family Stress Model (FSM) explains the mechanisms that mediate between families' structural conditions and children's developmental outcomes. Foundational works for this approach focus on historic events that instigate rapid structural changes which, in turn, undermine families' economic situation. The economic losses trigger stress processes. Research on the COVID-19 pandemic reports heightened levels of parental stress and negative impacts on children's cognitive and socioemotional development. This study examines the role of parental emotional distress during the COVID-19 shutdown on children's cognitive development. Expanding on the classical FSM, we hypothesize that changes in parents' working situation, rather than economic changes, may have triggered family stress processes during the shutdown, as federal support largely cushioned economic cutbacks in Germany. METHOD: For the German National Educational Panel Study (NEPS), interviews were conducted with parents, and primary school students in Starting Cohort 1 were tested after the first shutdown in 2020. The database provides rich information from survey waves prior to the COVID-19 pandemic, allowing a longitudinal analysis of a sample of 1512 primary school students with ordinary least squares regression. RESULTS: Parents' emotional distress during the pandemic had a robust negative effect on students' mathematical skills, even when controlling for prior parenting stress. Changes in parents' working conditions also had an effect on children's test scores, and the negative effect of working from home on the test scores was mediated by parents' emotional distress. CONCLUSION: The COVID-19 pandemic was a historic event which, at least in Germany, challenged the mental health of many parents and, in turn, impaired the skill development of primary school students. We introduce the role of changes in working conditions as triggers of such processes.
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COVID-19 , Desenvolvimento Infantil , Pais , Estresse Psicológico , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Alemanha/epidemiologia , Criança , Masculino , Feminino , Pais/psicologia , Estresse Psicológico/psicologia , Estresse Psicológico/epidemiologia , SARS-CoV-2 , Estudantes/psicologia , Instituições Acadêmicas , Adulto , MatemáticaRESUMO
This paper provides new evidence on inequalities in resources for children age 3-4 by parental education using harmonized data from six advanced industrialized countries-United States, United Kingdom, France, Germany, Netherlands, and Japan-that represent different social welfare regime types. We analyze inequalities in two types of resources for young children-family income, and center-based child care-applying two alternative measures of parental education-highest parental education, and maternal education. We hypothesize that inequalities in resources by parental education will be less pronounced in countries where social policies are designed to be more equalizing. The results provide partial support for this hypothesis: the influence of parental education on resources for children does vary by the social policy context, although not in all cases. We also find that the measurement of parental education matters: income disparities are smaller under a maternal-only definition whereas child care disparities are larger. Moreover, the degree of divergence between the two sets of estimates differs across countries. We provide some of the first systematic evidence about how resources for young children vary depending on parents' education and the extent to which such inequalities are buffered by social policies. We find that while early inequalities are a fact of life in all six countries, the extent of those inequalities varies considerably. Moreover, the results suggest that social policy plays a role in moderating the influence of parental education on resources for children.
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We examined whether inaccurate teacher judgements of primary school student achievement correlate with students' gender and whether such bias contributes to gender achievement gaps in language and mathematics. Our study used ex-post harmonised longitudinal data from England, Germany, and the US. We observed domain-specific teacher judgement bias with a positive bias for girls in the language domain and for boys in mathematics. Furthermore, biased teacher judgements partly mediated the effect of gender on later achievement. Despite these common findings, cross-country differences emerged in the extent of teacher judgement bias as well as its mediation of gender achievement gaps. We conclude that this is a topic of relevance across national contexts and where the institutional and societal setting needs more attention in future research.
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Sucesso Acadêmico , Julgamento , Masculino , Feminino , Humanos , Escolaridade , Inglaterra , AlemanhaRESUMO
Thin films of NaNbO3 were grown on various substrates to investigate the effect of epitaxial strain on their structural and electrical properties. Reciprocal space maps confirmed the presence of epitaxial strain from +0.8% to -1.2%. A bulk-like antipolar ground state was detected via structural characterization for NaNbO3 thin films grown with strains ranging from a compressive strain of 0.8% to small tensile strains, up to -0.2%. For larger tensile strains on the other hand, no indication of antipolar displacements can be detected, even beyond the relaxation of the film at larger thicknesses. Electrical characterization revealed a ferroelectric hysteresis loop for thin films under a strain of +0.8% to -0.2%, while the films under larger tensile strain showed no out-of-plane polarization component. However, the films with a compressive strain of 0.8% present a saturation polarization of up to 55 µC·cm-2, more than twice as large for films grown under conditions with small strain, which is also larger than the highest values reported for bulk materials. Our results indicate the high potential for strain engineering in antiferroelectric materials, as the antipolar ground state could be retained with compressive strain. The observed enhancement of the saturation polarization by strain allows for substantial increase of energy density of the capacitors with antiferroelectric materials.
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Socioeconomic inequalities in childhood Body Mass Index (BMI) are becoming increasingly more pronounced across the world. Although countries differ in the direction and strength of these inequalities, cross-national comparative research on this topic is rare. This paper draws on harmonized longitudinal cohort data from four wealthy countries-Germany, the Netherlands, the United Kingdom (UK), and the United States (US)-to 1) map cross-country differences in the magnitude of socioeconomic inequalities in childhood BMI, and 2) to examine cross-country differences in the role of three energy-balance-related behaviors-physical activity, screen time, and breakfast consumption-in explaining these inequalities. Children were aged 5-7 at our first timepoint and were followed up at age 8-11. We used data from the German National Educational Panel Study, the Dutch Generation R study, the UK Millennium Cohort Study and the US Early Childhood Longitudinal-Kindergarten Study. All countries revealed significant inequalities in childhood BMI. The US stood out in having the largest inequalities. Overall, inequalities between children with low versus medium educated parents were smaller than those between children with high versus medium educated parents. The role of energy-balance-related behaviors in explaining inequalities in BMI was surprisingly consistent. Across countries, physical activity did not, while screen time and breakfast consumption did play a role. The only exception was that breakfast consumption did not play a role in the US. Cross-country differences emerged in the relative contribution of each behavior in explaining inequalities in BMI: Breakfast consumption was most important in the UK, screen time explained most in Germany and the US, and breakfast consumption and screen time were equally important in the Netherlands. Our findings suggest that what constitutes the most effective policy intervention differs across countries and that these should target both children from medium as well as low educated families.
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Índice de Massa Corporal , Criança , Humanos , Pré-Escolar , Países Baixos , Estudos de Coortes , Fatores Socioeconômicos , Reino Unido , AlemanhaRESUMO
BACKGROUND: Electronic brachytherapy (eBT) is considered a safe treatment with good outcomes. However, eBT lacks standardized and independent dose verification, which could impede future use. PURPOSE: To validate the 3D dose-to-water distribution of an electronic brachytherapy (eBT) source using a small-volume plastic scintillation detector (PSD). METHODS: The relative dose distribution of a Papillon 50 (P50) (Ariane Medical Systems, UK) eBT source was measured in water with a PSD consisting of a cylindrical scintillating BCF-12 fiber (length: 0.5 mm, Ø: 1 mm) coupled to a photodetector via an optical fiber. The measurements were performed with the PSD mounted on a motorized stage in a water phantom (MP3) (PTW, Germany). This allowed the sensitive volume of the PSD to be moved to predetermined positions relative to the P50 applicator, which pointed vertically downward while just breaching the water surface. The percentage depth-dose (PDD) was measured from 0 to 50 mm source-to-detector distance (SDD) in 1-3 mm steps. Dose profiles were measured along two perpendicular axes at five different SDDs with step sizes down to 0.5 mm. Characterization of the PSD consisted of determining the energy correction through Monte Carlo (MC) simulation and by measuring the stability and dose rate linearity using a well-type ionization chamber as a reference. The measured PDD and profiles were validated with corresponding MC simulations. RESULTS: The measured and simulated PDD curves agreed within 2% (except at 0 mm and 43 mm depth) after the PSD measurements were corrected for energy dependency. The absorbed dose decreased by a factor of 2 at 7 mm depth and by a factor of 10 at 26 mm depth. The measured dose profiles showed dose gradients at the profile edges of more than 50%/mm at 5 mm depth and 15%/mm at 50 mm depth. The measured profile widths increased 0.66 mm per 1 mm depth, while the simulated profile widths increased 0.74 mm per 1 mm depth. An azimuthal dependency of > 10% was observed in the dose at 10 mm distance from the beam center. The total uncertainty of the measured relative dose is < 2.5% with a positional uncertainty of 0.4 mm. The measurements for a full 3D dose characterization (PDD and profiles) can be carried out within 8 h, the limiting factor being cooling of the P50. CONCLUSION: The PSD and MP3 water phantoms provided a method to independently verify the relative 3D dose distribution in water of an eBT source.
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Braquiterapia , Eletrônica , Método de Monte Carlo , Plásticos , Radiometria , ÁguaRESUMO
Gaps in language skills by socio-economic status (SES) are already evident before school entry, and these gaps may change over time. After discussing mechanisms of cumulative advantages ('Matthew effects') and compensatory effects as well as the relevance of cultural capital and child-related activities in families, this paper tests mechanisms behind changing SES gaps in language skills from age five to nine in Germany. Analysing data from the German National Educational Panel Study with growth curve models, we find widening SES gaps in children's vocabulary. Children of mothers with low educational attainment show a far below-average increase in skills. The findings are in line with cumulative advantage by status, although initial skills predict their growth over time as well. There are no signs of any type of compensatory effects. Reading aloud to children appears to substantially impact and mediate SES differences in vocabulary progress.
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Idioma , Vocabulário , Feminino , Humanos , Desenvolvimento da Linguagem , Relações Pais-Filho , Classe SocialRESUMO
Prostate brachytherapy treatment using permanent implantation of low-energy (LE) low-dose rate (LDR) sources is successfully and widely applied in Europe. In addition, seeds are used in other tumour sites, such as ophthalmic tumours, implanted temporarily. The calibration issues for LE-LDR photon emitting sources are specific and different from other sources used in brachytherapy. In this report, the BRAPHYQS (BRAchytherapy PHYsics Quality assurance System) working group of GEC-ESTRO, has developed the present recommendations to assure harmonized and high-quality seed calibration in European clinics. There are practical aspects for which a clarification/procedure is needed, including aspects not specifically accounted for in currently existing AAPM and ESTRO societal recommendations. The aim of this report has been to provide a European wide standard in LE-LDR source calibration at end-user level, in order to keep brachytherapy treatments with high safety and quality levels. The recommendations herein reflect the guidance to the ESTRO brachytherapy users and describe the procedures in a clinic or hospital to ensure the correct calibration of LE-LDR seeds.
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Braquiterapia/métodos , Fótons/uso terapêutico , Calibragem , Hospitais , Humanos , Dosagem RadioterapêuticaRESUMO
OBJECTIVE: This study examines how changes in cohabitation or marital status affect Body Mass Index (BMI) over time in a large representative sample. METHOD: Participants were 20,950 individuals (50% female; 19 to 100 years), representative of the German population, who provided 81,926 observations over 16 years. Face-to-face interviews were used to obtain demographic data, including cohabitation and marital status, height, body weight, and weight-relevant behaviors (exercise, healthy eating, and smoking). Control variables included age, notable changes in status (life events such as having children or change in employment status), perceived stress, and subjective health. RESULTS: Cohabitation led to significant weight gain in men and women-after four years or longer, about twice the gain associated with marriage (controlling for weight-related behaviors, age, children, employment, stress, and health). BMI after separation was largely comparable to BMI before starting cohabitation; women lost some weight in the first year, men gained some weight after four or more years of separation. Divorce generally predicted weight gain. Changes in exercise, healthy eating, and smoking did not attenuate the effect of changes in relationship status on BMI. CONCLUSIONS: This is among the first longitudinal studies to directly compare the effects of key changes in relationship status on BMI. The findings extend and qualify previous results by showing that the benefits of marriage or cohabitation do not necessarily include a healthier BMI. They also suggest that relationship transitions-particularly moving in with a partner and divorce-may be important time windows for weight gain prevention. (PsycINFO Database Record
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Índice de Massa Corporal , Divórcio/psicologia , Casamento/psicologia , Parceiros Sexuais , Adulto , Peso Corporal/fisiologia , Dieta Saudável , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fumar , Aumento de Peso/fisiologiaAssuntos
Implantes Absorvíveis , Angioplastia Coronária com Balão , Aneurisma Coronário/cirurgia , Angiografia Coronária , Implantes Absorvíveis/efeitos adversos , Idoso , Angioplastia Coronária com Balão/métodos , Aneurisma Coronário/diagnóstico , Angiografia Coronária/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoAssuntos
Envelhecimento/psicologia , Atitude Frente a Saúde , Qualidade de Vida , Autoimagem , Feminino , Humanos , MasculinoRESUMO
A large air-filled parallel-plate extrapolation chamber in a phantom of water-equivalent material is used as a primary standard measuring device for low-energy interstitial brachytherapy sources from which the unit of absorbed dose to water can be derived. The chamber is suitable for low-energy photons with energies up to 50 keV. The method to determine the absorbed dose to water was newly developed based on radiation transport theory. It offers a clear analytical expression to determine D(w). A conversion factor C(x(i),x(i)(+1)) has to be applied to the difference of ionization charges measured at two plate separations x(i) and x(i)(+1). The details of the method are presented. The determination of D(w) of an I-125 seed is demonstrated by the measurement of a 'BEBIG Symmetra I25.S16' - seed. Additional measurements of the reference air kerma rate with the PTB primary standard chamber GROVEX I allow to determine experimentally the dose rate constant of an I-125 seed by means of primary standards for the first time. Good agreement was found between the obtained dose rate constant and the published data.
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Braquiterapia/métodos , Radioisótopos do Iodo/uso terapêutico , Radiometria/instrumentação , Absorção , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Dosagem Radioterapêutica , Análise Espectral/métodos , ÁguaRESUMO
OBJECTIVES: To assess the feasibility to place a left ventricular lead into the coronary sinus following percutaneous mitral annuloplasty. BACKGROUND: Percutaneous coronary sinus-based mitral annuloplasty may reduce functional mitral regurgitation in chronic systolic heart failure. However, concerns have been raised whether the placement of an annular remodeling device in the coronary sinus might preclude subsequent lead placement for resynchronization therapy (CRT). METHODS: Three patients with ischemic cardiomyopathy included in the AMADEUS trial underwent CRT 7 to 8 months after implantation of a mitral valve annuloplasty device. RESULTS: Fluoroscopy and control coronary angiography revealed a stable position of the annuloplasty device without any compromise of coronary blood flow. Intravascular ultrasound of the coronary sinus excluded any thrombus formation and demonstrated smooth endothelialization of the annular remodeling device. Access of the coronary sinus and placement of the left ventricular lead into a posterolateral cardiac vein was not at all compromised by the mitral valve annuloplasty device in any patient. CONCLUSIONS: Positioning a left ventricular pacing lead for CRT is feasible after permanent implantation of a coronary sinus-based mitral annuloplasty device in patients with dilated cardiomyopathy.
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Cateterismo Cardíaco/instrumentação , Seio Coronário , Cardioversão Elétrica , Insuficiência Cardíaca Sistólica/terapia , Insuficiência da Valva Mitral/terapia , Idoso , Cateterismo Cardíaco/efeitos adversos , Angiografia Coronária , Circulação Coronária , Seio Coronário/diagnóstico por imagem , Seio Coronário/fisiopatologia , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Desenho de Equipamento , Estudos de Viabilidade , Insuficiência Cardíaca Sistólica/complicações , Insuficiência Cardíaca Sistólica/diagnóstico , Insuficiência Cardíaca Sistólica/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/fisiopatologia , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção , Função Ventricular EsquerdaRESUMO
AIMS: Cardiovascular risk factors are associated with decreased levels of circulating progenitor cells (CPC). The aim of this study was to determine whether the number of CPC is an independent correlate of body mass index (BMI) and whether weight loss leads to an increase in CPC. METHODS AND RESULTS: CD34 positive and KDR/CD34, CD133/CD34, and CD117/CD34 double positive cells were measured by fluorescence activated cell sorting (FACS) analysis in peripheral blood of 149 volunteers (52.5 +/- 12.0 years, BMI 21.5-52.7 kg/m(2), mean 31.6 +/- 5.1 kg/m(2)) participating in a weight reduction program offered by German pharmacies. In addition, carotid intima media thickness (IMT) and brachial artery flow-mediated dilatation were determined. After a diet and sports program for 6 months, 86 representing subjects were re-evaluated (mean weight loss 5.8 +/- 5.2 kg). There was an inverse correlation between BMI as well as waist circumference and CPC, especially CD34 positive, KDR/CD34 positive, CD133/CD34 positive, and CD117/CD34 positive cells. This decrease in CPC in obesity held true not only for the absolute cell numbers, but also for the relative fractions of KDR, CD133, and CD117 positive cells within the CD34 positive cells, indicating a specific down regulation of these progenitor cell types. Multiple regression analysis revealed that BMI was a more prominent predictor of CPC regulation than blood pressure, LDL cholesterol, triglycerides, fasting glucose, and smoking. IMT increased in dependence on BMI (P < 0.001) and was inversely correlated with the number of CD34 positive cell (P < 0.05). After diet, there was a significant increase of CD34 and CD117/CD34 positive cells, which correlated with the decrease in BMI. Also, weight loss was accompanied by a decrease in IMT (P = 0.015), which also correlated with the increase in CPC (P < 0.001). The increase in the number of CPC was independent from whether weight loss was achieved by increased physical exercise or by reduced calorie intake only. CONCLUSION: Obesity is associated with decreased numbers of CPC and increased IMT. Diet and weight loss lead to an increase in CPC count, which might contribute to regression of IMT.
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Dieta Redutora , Obesidade/dietoterapia , Células-Tronco/citologia , Redução de Peso/fisiologia , Adolescente , Adulto , Idoso , Antígenos CD34/metabolismo , Arteriosclerose/patologia , Índice de Massa Corporal , Separação Celular , Métodos Epidemiológicos , Feminino , Citometria de Fluxo/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/patologia , Túnica Íntima/patologiaRESUMO
The mutation of well behaved enzymes in order to simulate less manageable cognates is the obvious approach to study specific features of the recalcitrant target. Accordingly, the prototypical protein kinase PKA serves as a model for many kinases, including the closely related PKB, an AGC family protein kinase now implicated as oncogenic in several cancers. Two residues that differ between the alpha isoforms of PKA and PKB at the adenine-binding site generate differing shapes of the binding surface and are likely to play a role in ligand selectivity. As the corresponding mutations in PKA, V123A would enlarge the adenine pocket, while L173M would alter both the shape and its electronic character of the adenine-binding surface. We have determined the structures of the corresponding double mutant (PKAB2: PKAalpha V123A, L173M) in apo and MgATP-bound states, and observed structural alterations of a residue not previously involved in ATP-binding interactions: the side-chain of Q181, which in native PKA points away from the ATP-binding site, adopts in apo double mutant protein a new rotamer conformation, which places the polar groups at the hinge region in the ATP pocket. MgATP binding forces Q181 back to the position seen in native PKA. The crystal structure shows that ATP binding geometry is identical with that in native PKA but in this case was determined under conditions with only a single Mg ion ligand. Surface plasmon resonance spectroscopy studies show that significant energy is required for this ligand-induced transition. An additional PKA/PKB mutation, Q181K, corrects the defect, as shown both by the crystal structure of triple mutant PKAB3 (PKAalpha V123A, L173M, Q181K) and by surface plasmon resonance spectroscopy binding studies with ATP and three isoquinoline inhibitors. Thus, the triple mutant serves well as an easily crystallizable model for PKB inhibitor interactions. Further, the phenomenon of Q181 shows how crystallographic analysis should accompany mutant studies to monitor possible spurious structural effects.
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Trifosfato de Adenosina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Técnicas Biossensoriais , Cristalografia por Raios X , Proteínas Quinases Dependentes de AMP Cíclico/química , Magnésio/metabolismo , Modelos Moleculares , Mimetismo Molecular , Dados de Sequência Molecular , Mutação , Conformação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-akt , Homologia de Sequência de Aminoácidos , Enxofre/químicaRESUMO
BACKGROUND: Although the use of premounted stents on a delivery balloon has almost completely eliminated the initially used hand-crimping procedure, no data are available that prove the superiority of one or the other approach on a randomized basis. Therefore, this study was designed to examine whether the use of premounted stents is comparable with the hand-crimping procedure. METHODS: A total of 123 patients (64 treated with unmounted stents, 59 treated with premounted stents) were examined in a multicenter, randomized, prospective study. There were no significant differences in patient characteristics between groups. RESULTS: Primary end points (acute, postinterventional [within 72 hours], and late complications related to the stenting procedure) were reached in 1 patient treated with an unmounted stent versus 2 patients with mounted stents (P = not significant). In patients with angiographic follow up (n = 84, mean follow-up period 6 +/- 1 months), the total rate of restenosis was 27% (unmounted 12, mounted 11, P = not significant). Secondary end points were procedural success of stenting and maximal balloon inflation pressure needed for optimal stenting results by use of angiography. There were no differences in secondary end points for both techniques. The mean balloon pressure was 12.56 +/- 2.1 atmospheres (unmounted) and 12.12 +/- 1.92 atmospheres (mounted, P = not significant). CONCLUSION: Stenting with premounted devices was demonstrated to have a similar clinical and angiographic outcome as the hand-crimping approach for maximal inflation pressure, procedural success, major cardiac events, and rate of restenosis after 6 months of follow up. Thus, the more convenient use of a premounted stent provides procedural safety and efficacy comparable with a hand-crimped system.
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Angioplastia Coronária com Balão/métodos , Estenose Coronária/terapia , Stents , Angioplastia Coronária com Balão/efeitos adversos , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Design de Software , Stents/efeitos adversosRESUMO
Highly soluble [(tBu(4)PcM)(2)O] phthalocyanine dimers (M=Ga(III) (3), In(III) (4)) were prepared by the reaction of [tBu(4)PcMCl] (M=Ga(III) (1), In(III) (2)) with excess of concentrated H(2)SO(4) at -20 degrees C. The Mbond;Obond;M linkages in 3 and 4 are not stable against concentrated H(2)SO(4) at room temperature, 6 n HCl at reflux, or during isolation under column chromatographic conditions (e.g. silica gel/toluene). The stability of 3 in solution is considerably higher than that of 4. The mu-oxo-bridged phthalocyanine dimers 3 and 4 have a more intense photoluminescence emission in the red region than the monomers 1 and 2. The gallium phthalocyanines 1 and 3 have fluorescence lifetimes of a few nanoseconds, while those of the indium phthalocyanines 2 and 4 last for only several hundred picoseconds. Comparison of the fluorescence lifetimes of monomers 1 and 3 with dimers 2 and 4, reveals that the dimers have longer lifetimes of the excited singlet states. The transient absorption spectrum is similar for all of the compounds, and the transient absorption band at about 520 nm, observed by nanosecond laser irradiation, can be assigned to the transition from the lowest triplet excited state to the upper triplet excited states (T-T absorption). The magnitude of the optical limiting exhibited by 1, 2, 3, and 4 in toluene at 532 nm laser pulse irradiation is in the order: 4>3>2>1 [corrected]. The values of the imaginary third-order nonlinear susceptibility Im[chi((3))] of the above compounds at 532 nm in toluene are also reported. These results demonstrate that these compounds are candidates for optical limiting applications.