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Evaporation of cloud droplets accelerates when turbulence mixes dry air into the cloud, affecting droplet-size distributions in atmospheric clouds, combustion sprays, and jets of exhaled droplets. The challenge is to model local correlations between droplet numbers, sizes, and supersaturation, which determine supersaturation fluctuations along droplet paths (Lagrangian fluctuations). We derived a statistical model that accounts for these correlations. Its predictions are in quantitative agreement with results of direct numerical simulations, and explain the key mechanisms at play.
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The behavioral response of the larval parasitoid Spintherus dubius (Hymenoptera: Pteromalidae) to volatile compounds derived from its Apion weevil hosts was investigated in two-choice bioassays. Odor source candidates were the larval and adult stages of weevils, clover flowers, and feces from adult weevils. Despite S. dubius being a larval parasitoid, the odor of weevil larvae isolated from the clover flowers was not attractive to female parasitoids. Surprisingly, S. dubius females were instead attracted by the odor from the feces of adult weevils. The female parasitoids were similarly attracted to the feces produced by the two main hosts, the red clover weevil (A. trifolii) and the white clover weevil (A. fulvipes). Chemical analysis of the volatile composition of feces produced by the two hosts revealed qualitatively similar odor profiles, correlating with the observed attraction by the parasitoid towards both odor sources. Some of the identified volatile compounds are commonly present in clover plant headspace fractions and may function as a kairomone to facilitate orientation by S. dubius to Apion-infested clover flowers. Larval and adult weevils were not attractive for parasitoid females, whereas, for the white clover weevil-plant association, infested flowers were highly attractive. These data show the use by the clover weevil parasitoid of an alternative source of olfactory information for locating its host.
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AIM: To study the effects of menopausal hormone therapy (HT) on health-related quality of life in women after breast cancer. PATIENTS AND METHODS: In the Stockholm trial, breast cancer survivors were randomized to HT (estradiol and progestogen) or to a control group (no treatment). A subgroup of 75 women was studied (38 with HT, 37 controls). Fifty patients were on concomitant tamoxifen. Patients completed three questionnaires (EORTC QLQ C-30, EORTC QLQ-BR 23 and the Hospital Anxiety and Depression Scale (HADS)) during 1 year of treatment. RESULTS: A significant group-by-time interaction was found for improvement of insomnia in the HT group (p < 0.001). Within the HT group, but not in the control group, there was significant improvement for HADS anxiety, HADS depression, emotional, cognitive, and social functions and global quality of life. When HT was added to tamoxifen, the increase in global quality of life was significant (p < 0.01). CONCLUSION: The effects of HT on quality of life in breast cancer survivors have not previously been reported. The present data suggest that this controversial treatment may improve quality of life after breast cancer.
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Neoplasias da Mama/psicologia , Terapia de Reposição Hormonal , Qualidade de Vida , Adulto , Idoso , Ansiedade/tratamento farmacológico , Neoplasias da Mama/terapia , Cognição , Depressão/tratamento farmacológico , Fadiga/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Inquéritos e Questionários , Suécia , Tamoxifeno/uso terapêuticoRESUMO
An analysis is presented of the first harmonic radar studies of pheromone-plume locating flights of male Agrotis segetum moths over distances of up to 500 m. Upon release most moths flew in a direction having a downwind component. The first significant changes in flight orientations occur in the immediate vicinity of a pheromone source. Moths that were initially flying downwind change course and start flying crosswind whilst those that initially flew crosswind change course and start flying upwind. It is shown that such behaviour is consistent with the adoption of an effective plume-location strategy, and conditions are identified when downwind flights would be more advantageous than crosswind ones. Additionally, some of the complex flight patterns that can arise at later times are shown to be compatible with the adoption of an optimal biased scale-free (Lévy-flight) searching strategy. It is found that disruptive doses of sex pheromone can have a marked influence upon male moth flight patterns.
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Voo Animal/fisiologia , Mariposas/fisiologia , Animais , Comportamento Animal , Masculino , Modelos Biológicos , Orientação , Atrativos Sexuais/fisiologia , Olfato/fisiologiaRESUMO
This paper summarises the results of the EU funded MEAD project, an interdisciplinary study of the effects of atmospheric nitrogen deposition on the Kattegat Sea between Denmark and Sweden. The study considers emissions of reactive nitrogen gases, their transport, transformations, deposition and effects on algal growth together with management options to reduce these effects. We conclude that atmospheric deposition is an important source of fixed nitrogen to the region particularly in summer, when nitrogen is the limiting nutrient for phytoplankton growth, and contributes to the overall eutrophication pressures in this region. However, we also conclude that it is unlikely that atmospheric deposition can, on its own, induce algal blooms in this region. A reduction of atmospheric nitrogen loads to this region will require strategies to reduce emissions of ammonia from local agriculture and Europe wide reductions in nitrous oxide emissions.
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Poluentes Atmosféricos , Eucariotos/crescimento & desenvolvimento , Eutrofização , Nitrogênio , Agricultura , Amônia , Disponibilidade Biológica , Biomassa , Dinamarca , Monitoramento Ambiental/métodos , Poluição Ambiental/prevenção & controle , Modelos Teóricos , Óxido Nitroso , Oceanos e Mares , Fitoplâncton/crescimento & desenvolvimento , Estações do Ano , SuéciaRESUMO
This paper describes a modelling approach for evaluating the efficiency of different non-structural best management practices for stormwater management. A scenario with a set of source reduction practices was simulated using the substance flow model SEWSYS for an urban catchment in the city of Göteborg, Sweden. The scenario is based on a hypothetical control program that includes prevention, education and regulations. The simulation shows relatively high reductions of copper and PAH, 77% and 50%, respectively. The reduction in copper is mainly due to less copper roof corrosion and brake wear, while reduced road wear has the greatest effect for PAH. An important result from this study is that the nonstructural BMPs applied did not give a sufficient reduction in pollution to meet the desirable environmental quality criteria. To meet these criteria, additional BMPs must be implemented, preferably a combination of both non-structural and structural measures.
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Modelos Teóricos , Eliminação de Resíduos Líquidos/métodos , Poluição da Água/análise , Poluição da Água/prevenção & controle , Conservação dos Recursos Naturais , Cobre/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Controle de Qualidade , Chuva , Valores de ReferênciaRESUMO
The effect of retrofitting an existing pond on removal efficiency and hydraulic performance was modelled using the commercial software Mike21 and compartmental modelling. The Mike21 model had previously been calibrated on the studied pond. Installation of baffles, the addition of culverts under a causeway and removal of an existing island were all studied as possible improvement measures in the pond. The subsequent effect on hydraulic performance and removal of suspended solids was then evaluated. Copper, cadmium, BOD, nitrogen and phosphorus removal were also investigated for that specific improvement measure showing the best results. Outcomes of this study reveal that all measures increase the removal efficiency of suspended solids. The hydraulic efficiency is improved for all cases, except for the case where the island is removed. Compartmental modelling was also used to evaluate hydraulic performance and facilitated a better understanding of the way each of the different measures affected the flow pattern and performance. It was concluded that the installation of baffles is the best of the studied measures resulting in a reduction in the annual load on the receiving lake by approximately 8,000 kg of suspended solids (25% reduction of the annual load), 2 kg of copper (10% reduction of the annual load) and 600 kg of BOD (10% reduction of the annual load).
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Modelos Teóricos , Eliminação de Resíduos Líquidos/métodos , Oxigênio/metabolismo , Chuva , Software , Movimentos da Água , Poluentes da Água/análise , Abastecimento de ÁguaRESUMO
The performance of stormwater ponds, operated under winter conditions, was modelled using the commercial software Mike21 and MOUSE. Direct and indirect effects of changing temperature were investigated. The most important effect of winter conditions is the changed hydrology, characterised by long periods with no runoff followed by snowmelt events with large runoff volumes during several days. This gives lower removal efficiencies than during a period with the same precipitation but without winter conditions. For the concentration of dissolved oxygen, wind is an important factor. Consequently the most important effect of an ice cover on the pond is that it prevents the oxygenation effects of the wind. The direct temperature effects on the removal processes are negligible compared to the indirect effects in changed hydrology and forming of ice cover.
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Temperatura Baixa , Modelos Teóricos , Oxigênio/análise , Eliminação de Resíduos Líquidos/métodos , Clima , Gelo , Estações do Ano , Neve , Abastecimento de ÁguaRESUMO
During recent years the interest in street sweeping as a pollutant control measure has increased. For planning of street sweeping programs and disposal of street sweeping waste there is a need to investigate the composition of street sweeping waste and the effect of street sweeping on the remaining sediments on the street. Particle size distribution and heavy metal concentration has been measured for street sweeping waste, street sediments before sweeping and remaining sediments after sweeping. The results show that the concentrations of heavy metals are a function of particle diameter and proportional to the inverse of the particle diameter, i.e. the highest concentrations are found in finest fractions. Regression equations for metal concentrations as a function of particle diameter are presented. According to Swedish guidelines for environmental quality of contaminated sites, heavy metal concentration in the sweeping waste can not be considered as a serious problem. The largest amount of metals and sediment is found in the sandy fractions (0.125-0.5 mm). The street sweeper is more effective in removing coarse sediments than fine. This means that the street sediments after sweeping are finer than the sediments before.
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Sedimentos Geológicos/química , Metais Pesados/análise , Emissões de Veículos/análise , Cidades , Monitoramento Ambiental , Tamanho da Partícula , Chuva , Dióxido de Silício , Movimentos da ÁguaRESUMO
OBJECTIVE: Early aortic insufficiency can be a problem after the Ross procedure. Anatomical mismatch and an inexact surgical technique may lead to distortion of the normal pulmonary valve geometry and subsequent incorrect leaflet coaptation and valve insufficiency. In this study, we assessed the efficacy of changing and improving the surgical technique to minimize the early pulmonary autograft valve failure. The modifications and the strategy are discussed. METHODS: From January 1995 to February 1999, a total of 77 adults underwent the Ross procedure for aortic valve replacement at Sahlgrenska University Hospital. The operative technique used was full free-standing aortic root replacement with a pulmonary autograft in all cases. In the first 24 cases, the diameter of the pulmonary roots was seldom measured, eye-balling was used to exclude anatomical mismatch due to a dilated aortic root, and only one attempt of correction was made, which failed. In the other 53 cases, the technique was improved by: (1) reducing the aortic anulus diameter in cases with moderate dilatation; (2) excluding cases with severe dilatation of the aortic annulus; (3) adjusting the diameter of the sinotubular junction of the aorta to the diameter of the sinotubular junction of the pulmonary artery; (4). reimplanting the left ostium in the autograft, and (5) changing the proximal anastomosis technique. RESULTS: In this study, we had an early aortic incompetence of grade 2 in eight patients among the first 24 patients. In the other 53 patients, postoperative echocardiography at 1 week revealed aortic insufficiency of grade 2 in two patients. CONCLUSIONS: Aortic insufficiency after the Ross procedure can be minimized by patient selection, intraoperative correction of anatomical mismatch and improved surgical technique.
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Insuficiência da Valva Aórtica/etiologia , Valva Aórtica/cirurgia , Complicações Pós-Operatórias , Valva Pulmonar/transplante , Adolescente , Adulto , Idoso , Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/diagnóstico por imagem , Procedimentos Cirúrgicos Cardíacos/métodos , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Hepatitis C is frequent problem in dialysis wards. DESIGN: A long time (1989-97) follow up of hepatitis C virus (HCV) infection in a Swedish nephrology unit was performed with anti-HCV screening, confirmatory antibody tests, viral RNA detection and molecular characterization. Case histories were reviewed with focus, onset of infection, liver morbidity and mortality. RESULTS: In October 1991, 10% (19 of 184) of the patients in the unit (haemodialysis-, peritoneal dialysis and transplanted patients) were verified or suspected HCV carriers, whilst the number at the end of 1996 was 8%, (13 of 157). Most patients were infected before 1991 but only in one case from a known HCV-infected blood donor. No new HCV infections associated with haemodialysis occurred during the study period. A total of 13 of 24 viremic patients had HCV genotype 2b, a pattern suggesting nosocomial transmission. This was further supported by phylogenetic analysis of HCV viral isolates in seven. HCV viremia was also common in patients with an incomplete anti-HCV antibody pattern as 8 of the 12 indeterminant sera were HCV-RNA positive. CONCLUSIONS: Awareness, prevention, identification of infected patients and donor testing limited transmission. Indeterminant recombinant immunoblot assays (RIBA)-results should be regarded with caution as a result of the relative immunodeficiency in uremic patients. Our data indicate nosocomial transmission in several patients.
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Hepatite C/diagnóstico , Transplante de Fígado , Diálise Renal , Adolescente , Adulto , Idoso , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/mortalidade , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/mortalidade , Hepatite C/prevenção & controle , Hepatite C/transmissão , Anticorpos Anti-Hepatite C/sangue , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Viral/sangue , Fatores de Risco , Taxa de Sobrevida , SuéciaRESUMO
An indoor mating disruption experiment was performed on the stored-product pest Plodia interpunctella. The female of this species emits a four-component pheromone blend consisting of Z9,E12-14 : OAc, Z9,E12-14 : OH, Z9,E12-14 : Ald, and Z9-14 : OAc. Mating of Plodia interpunctella was disrupted up to 93% by using synthetic pheromone in small-scale plot experiments. The study was performed in 2.5 m x 2.5 m x 2.5 m polythene cubicles housed in a greenhouse, and pheromones were released by MSTRS spraying every 15 min. The disruption effect was tested at different doses 0.075, 0.75, and 3.75 mg/spray (corresponding to 5, 50, and 250 microg/min), different pheromone formulas (one-component (Z9,E12-14 : OAc) and four-component), and at different population densities (10, 20, and 30 individuals, equivalent to 0.32, 0.64, and 0.96 individuals/m2). The moths were released into the cubicles and recaptured 24 hr later. The females were checked for spermatophore presence indicating successful mating. The mating was significantly suppressed in all treatments compared to the control. There was, however, no difference in mating activity between the one-component and four-component disruptants. In addition, EAG measurements were conducted with a portable device to keep track of aerial concentrations of pheromone. The results show that the one-component formula disrupts mating as efficiently as the more complete four-component blend at doses applied in this study. This fact improves the prospects for mating disruption of indoor pyralids, since many pyralid species share the major component in their pheromones, and, thus, can probably be controlled simultaneously by using this compound only.
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Lepidópteros , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal , Animais , Eletrofisiologia , Feminino , Masculino , Controle de Pragas , Dinâmica PopulacionalRESUMO
Sharing scientific data containing complex information requires new concepts and new technology. NEUROGENERATOR is a database generator for the neuroimaging community. A database generator is a database that generates new databases. The scientists submit raw PET and fMRI data to NEUROGENERATOR, which then processes the data in a uniform way to create databases of homogeneous data suitable for data sharing, met-analysis and modelling the human brain at the systems level. These databases are then distributed to the scientists.
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Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Bases de Dados Factuais , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada de EmissãoRESUMO
Pressure recovery has been described in aortic stenosis and may explain the difference occasionally observed between Doppler- and catheter-measured gradients. A narrow ascending aorta (AA) and moderately severe stenosis favors pressure recovery. The aims of this study were to investigate the degree to which these conditions are present in patients with aortic stenosis and high Doppler gradients and to evaluate the magnitude of pressure recovery. One hundred sixteen patients were examined with Doppler echocardiography before aortic valve replacement. Patients with a maximum gradient >70 mm Hg (n = 81) were included. The diameter of the AA was measured and compared with the diameter in an age- and body size-matched group of normal controls (n = 23). Pressure recovery was estimated from a previously validated equation by measuring the maximum Doppler gradient, the effective orifice area (EOA), and the diameter of the AA. The diameter of the AA was similar for patients (mean 3.0 cm, range 2.1 to 4.1) and normal controls (mean 3.0 cm, range 2.3 to 3.5). The maximum Doppler gradient was 107 mm Hg (range 71 to 170) and the EOA was 0.6 cm(2) (range 0.2 to 1.3). The calculated pressure recovery was 18 mm Hg (range 6 to 37), which gives a net gradient of 89 mm Hg (range 51 to 151). Twenty-three percent had a net gradient <70 mm Hg. A cutoff of EOA/AA diameter at >0.2 cm identified 84% of patients (16 of 19) with a net gradient <70 mm Hg. In conclusion, we found that important pressure recovery can be expected in most patients with aortic stenosis and high Doppler gradients. Pressure recovery may explain why some patients with high Doppler gradients are asymptomatic. Also, pressure recovery is a factor to consider in patients with atypical symptomatology and high Doppler gradients when one must decide on valvular replacement.
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Estenose da Valva Aórtica/diagnóstico por imagem , Ecocardiografia Doppler , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Estudos de Casos e Controles , Feminino , Implante de Prótese de Valva Cardíaca , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Estudos RetrospectivosRESUMO
OBJECTIVE: To analyse the difference in bone mineral content (BMC) between the left and right trunk generally obtained by dual-energy X-ray absorptiometry (DXA) by creating identical images over the liver region and the contralateral side. PATIENTS AND DESIGN: Fifty-four patients were selected at random from 1,722 subjects examined by DXA because of osteoporosis. Another five patients were selected who had been followed for osteoporosis by repeated DXA two to five times at intervals from 2 to 36 months. One healthy volunteer was followed for one day by means of DXA total body measurements. All protocols were analysed with respect to BMC, fat mass (FM) and lean tissue mass (LTM) of the imaged trunk and liver. RESULTS: BMC of the right trunk exceeded that of the left trunk in 78% of the investigated subjects. The right (liver) image dominated in all 81 investigations calculated from 60 subjects. There were intraindividual short- and longterm variations between repeated DXA examinations. The amounts of FM and LTM were distributed symmetrically between the right and left trunk. CONCLUSIONS: DXA registers BMC in the liver, which explains the general dominance of the right trunk. The absorption over the liver region varies in the same individual in repeated measurements at intervals of hours to months.
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Absorciometria de Fóton , Densidade Óssea , Fígado/diagnóstico por imagem , Absorciometria de Fóton/métodos , Idoso , Composição Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose/fisiopatologia , Análise de RegressãoRESUMO
A structural model of potassium antimony germanate/silicate (0.32/0.68), KSbO(Ge(0.32)Si(0.68))O(4), has been determined at room temperature. KSbO(Ge(0.32)Si(0.68))O(4) belongs to the KTiOPO(4) (KTP) isomorphic family and is composed of SbO(6) octahedra (site symmetry -1 and 2) arranged in helical chains bridged by (Ge/Si)O(4) tetrahedra. Germanium and silicon have a similar distribution in the crystallographically independent tetrahedra (site symmetry 2). The structure contains large cavities occupied by the K atom. Two partially occupied potassium positions have been identified 1.273 (8) A apart, with an indication of a third potassium position between them. At room temperature, KSbO(Ge(0.32)Si(0.68))O(4) crystallizes in the paraelectric phase of space group Pnan. This phase is found at elevated temperatures for almost all KTiOPO(4) isomorphic compounds and KSbO(Ge(0.32)Si(0.68))O(4) is the second isomorph that is paraelectric at room temperature.
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A room-temperature structural model of titanium pyrophosphate, TiP(2)O(7), has been determined from synchrotron X-ray data. The structure consists of TiO(6) octahedra and PO(4) tetrahedra sharing corners in a three-dimensional network. The PO(4) tetrahedra form P(2)O(7) groups connecting the TiO(6) octahedra. The 3 x 3 x 3 superstructure differs substantially from the parent AB(2)O(7) structure. The P--O--P bonding angles of the pyrophosphate group are between 141.21 (12) and 144.51 (13) degrees for those groups not located on the threefold axis. The individual TiO(6) octahedra and PO(4) tetrahedra are somewhat distorted.
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This report describes patient tolerance and toxicity of a transrectal ultrasound hyperthermia system used with external beam radiation therapy in treatment of locally advanced prostate cancer. Nine patients with clinical T2B-T3B (4th edition AJCC criteria) disease received external beam radiation therapy, with two hyperthermia treatments scheduled at least 1 week apart during the first 4 weeks of radiation. Five patients also received hormonal therapy. Interstitial and anterior rectal wall thermometry were performed. Median temperature for each treatment (T50) was 40.8 degrees C and mean CEM T90 = 43 degrees C was 3.4 min. Rectal wall temperature was maintained at < or = 40 degrees C. Treatment duration was limited in three of 17 sessions due to positional discomfort which was alleviated with light IV sedation and use of a 'New Life' mattress (Comfortex, Inc. Winoba, MN, USA). Acute toxicity was limited to NCI common toxicity criteria grade 1 and no excess toxicity was noted with full course radiation therapy +/- hormonal therapy. These findings are consistent with those reported in a previous phase I trial assessing this device. Given the favourable toxicity profile demonstrated to date, modification of treatment parameters for this ongoing phase II study have been instituted that should further the efficacy of transrectal ultrasound hyperthermia for treatment of prostate cancer.
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Hipertermia Induzida/métodos , Neoplasias da Próstata/terapia , Terapia por Ultrassom/métodos , Idoso , Antineoplásicos Hormonais/uso terapêutico , Temperatura Corporal/efeitos da radiação , Terapia Combinada , Humanos , Hipertermia Induzida/efeitos adversos , Hipertermia Induzida/instrumentação , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Reto/efeitos da radiação , Terapia por Ultrassom/efeitos adversos , Terapia por Ultrassom/instrumentaçãoRESUMO
Structure factors for strontium/chromium- (Sr/Cr) and barium- (Ba) doped potassium titanyl phosphate (KTiOPO(4), KTP) were measured with focused synchrotron X-radiation [0.75000 (9) A] using a fast avalanche photodiode counter. Space group Pna2(1), Z = 8, a = 12.786 (2), b = 6.3927 (8), c = 10.5585 (9) A, T = 293 (1) K, R = 0.028 (SrCrKTP); a = 12.851 (6), b = 6.418 (3), c = 10.620 (5) A, T = 120 (1) K, R = 0.031 (BaKTP). The refinement of the dopant positions showed that Ba(2+) is positioned in the larger of the two K cavities of KTP, while the smaller Sr(2+) ion is located in both. Split positions are found for the strontium dopant in both cavities and they are located in the positive c direction from the potassium cation. The chromium dopant has two different oxidation states, namely +III and +VI; in both states the dopant is located inside the TiO(6) octahedra. The two structures show slightly less distorted TiO(6) octahedra than pure KTP.