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1.
Adv Physiol Educ ; 47(1): 117-123, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36546847

RESUMO

During the course of undergraduate studies, physiology (and related STEM) majors should acquire a both broad and in-depth foundation in physiological knowledge along with a distinct range of transferable (professional) skills (e.g., critical thinking, communication skills, data analysis). Previously, through a consultative and iterative process with physiology educators, the Professional Skills Committee of the Physiology Majors Interest Group (PMIG) defined and refined a consensus list of professional skills that physiology majors should acquire during their program of study. Here we describe the development and beta testing of a convenient tool to enable physiology and physiology-related program educators to map these professional skills across their curricula. The tool, referred to as PS-MAP, uses the Qualtrics platform and allows programs to collect and organize data about whether students are provided the opportunity to learn and develop the defined professional skills during their undergraduate experience. The authors have made the PS-MAP tool freely available to educators and provide practical tips for its implementation. Use of the PS-MAP tool and the data collected can help programs identify curricular strengths and gaps as well as facilitate curricular discussions among educators within the program.NEW & NOTEWORTHY In addition to foundational physiology knowledge, undergraduate physiology and related STEM majors should develop a range of transferable professional skills. However, evidence of this curricular goal has been lacking. Therefore, the Professional Skills Committee of the Physiology Majors Interest Group (PMIG) developed the freely available and convenient Physiology Professional Skills Curriculum Mapping Tool (PS-MAP) to assist educators in mapping these professional skills throughout their programs.


Assuntos
Currículo , Aprendizagem , Humanos , Estudantes , Pensamento
2.
J Dairy Sci ; 105(5): 4643-4652, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35221066

RESUMO

Prostaglandins are involved in multiple processes important for fertility, with previous work in mice highlighting a potential role for the HSD17B12 gene in prostaglandin biosynthesis. This study aimed to determine the associations among circulating prostaglandin concentrations, a missense SNP in the HSD17B12 gene predicted to disrupt protein function, and fertility traits in first-lactation Holstein-Friesian dairy cows. We used a study population of approximately 500 animals specifically bred to have either a positive (POS, +5%) or negative (NEG, -5%) genetic merit for fertility (FertBV). Genotypes of a previously identified SNP (rs109711583) in HSD17B12 were determined, with 116 animals genotyped as AA, 215 genotyped as AG, and 153 genotyped as GG. Plasma concentrations of prostaglandin E2 and the PGF2α metabolite PGFM were determined at 3 time points (12 mo of age, 4 d postpartum, and 5 wk postpartum during first lactation) in a selection of animals with AA and GG genotypes from both the POS and NEG FertBV groups (n = 33-40 in each genotype for each FertBV group). Binary reproductive traits (yes or no) examined included submission for artificial breeding in the first 3 or 6 wk of the seasonal breeding period; conception to first service; conception during the first 6 wk of the breeding period; and pregnant at the end of the breeding period. Uterine health at 6 wk after calving was examined by evaluating the percentage of polymorphonuclear leukocytes following uterine cytology and by scoring vaginal discharge based on the presence of purulent material. The 3-wk submission rate was increased in animals that carried the G allele of the missense SNP in HSD17B12, but no differences were present among genotypes for 6-wk submission rate. The trait was additive, with each increase of the G allele increasing the 3-wk submission rate by 6 to 7%. We did not observe any consistent associations between SNP alleles and circulating PGE2 concentrations; however, a complex 3-way interaction among time, fertility group, and SNP allele was present for PGFM concentrations. Plasma concentrations of PGE2 were increased approximately 40% at 5 wk postpartum in animals that were submitted for breeding within 3 or 6 wk of the start of the breeding season, and in those that conceived during the first 6 wk of breeding, compared with those that did not. Plasma concentrations of PGFM were decreased approximately 20% in those animals that conceived to their first service and tended to be decreased in animals that were pregnant at the end of the breeding period, compared with those that were not. In summary, associations were observed between the SNP in HSD17B12 and submission rate by d 21 of the breeding season, as well as between circulating prostaglandin concentrations and fertility traits, but the SNP was not consistently linked to changes in prostaglandin concentrations. Thus, the association between submission rate by d 21 of the breeding season and the SNP in HSD17B12 were unlikely driven by changes in prostaglandins.


Assuntos
Polimorfismo de Nucleotídeo Único , Prostaglandinas , 17-Hidroxiesteroide Desidrogenases/genética , Animais , Bovinos , Feminino , Fertilidade/genética , Lactação/genética , Gravidez , Prostaglandinas E , Reprodução/genética
3.
Phys Rev Lett ; 126(2): 025003, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33512205

RESUMO

Ammonia is predicted to be one of the major components in the depths of the ice giant planets Uranus and Neptune. Their dynamics, evolution, and interior structure are insufficiently understood and models rely imperatively on data for equation of state and transport properties. Despite its great significance, the experimentally accessed region of the ammonia phase diagram today is still very limited in pressure and temperature. Here we push the probed regime to unprecedented conditions, up to ∼350 GPa and ∼40 000 K. Along the Hugoniot, the temperature measured as a function of pressure shows a subtle change in slope at ∼7000 K and ∼90 GPa, in agreement with ab initio simulations we have performed. This feature coincides with the gradual transition from a molecular liquid to a plasma state. Additionally, we performed reflectivity measurements, providing the first experimental evidence of electronic conduction in high-pressure ammonia. Shock reflectance continuously rises with pressure above 50 GPa and reaches saturation values above 120 GPa. Corresponding electrical conductivity values are up to 1 order of magnitude higher than in water in the 100 GPa regime, with possible significant contributions of the predicted ammonia-rich layers to the generation of magnetic dynamos in ice giant interiors.

4.
Br J Anaesth ; 119(2): 221-230, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28854534

RESUMO

BACKGROUND: Anaesthetists use dexamethasone principally for its anti-emetic effect. The purpose of this study was to characterize the effects of a single intraoperative dose of dexamethasone on cellular and metabolic components of the immune system in patients undergoing laparoscopic surgical procedures. METHODS: In this prospective double-blind trial, female patients undergoing elective major laparoscopic surgery were randomized to receive saline (Control group, n =16) or dexamethasone 4 mg (Dexamethasone group, n =16) i.v. after the induction of anaesthesia. Inflammatory markers and immune cell counts were examined at 24 and 48 h and 6 weeks after surgery. The changes from baseline preoperative values were compared between groups using a Mann-Whitney U -test, and linear mixed models were used to validate the findings. RESULTS: No differences in concentrations of serum glucose and interleukin-6 were observed between groups after surgery. The increase in C-reactive protein concentration at 24 h after surgery was greater in the control group [median (interquartile range), 33 (25-65) vs 17 (7-26) mg dl -1 ; P =0.018]. Extensive changes in the counts of white cells, including most lymphocyte subsets, were observed 24 h after surgery, and dexamethasone appeared to attenuate most of these changes. Changes at 48 h and 6 weeks did not differ between groups. CONCLUSIONS: In female patients undergoing elective laparoscopic gynaecological surgery, dexamethasone administration appears to attenuate inflammation and to alter immune cell counts at 24 h, with no effects identified after this time. The importance of these changes for postoperative immune function is unknown. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Registry (ACTRN12608000340336).


Assuntos
Antieméticos/farmacologia , Dexametasona/farmacologia , Procedimentos Cirúrgicos Eletivos , Procedimentos Cirúrgicos em Ginecologia , Laparoscopia , Leucócitos/efeitos dos fármacos , Adulto , Glicemia/análise , Método Duplo-Cego , Feminino , Humanos , Período Intraoperatório , Leucócitos/imunologia , Pessoa de Meia-Idade , Estudos Prospectivos
5.
J Helminthol ; 89(1): 105-11, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24103656

RESUMO

Generally, women residing in areas endemic for urinary schistosomiasis may suffer from female genital schistosomiasis which is acquired during childhood. The objective of this cross-sectional study was to estimate the prevalence and intensity of infection of Schistosoma haematobium in women of reproductive age (16-45 years) and to investigate whether S. haematobium had any effect on kidney function. A total of 394 women of known pregnancy status (158 pregnant and 236 non-pregnant) were recruited from five villages (known for their high prevalence of infection of S. haematobium) in Kwale County. Serum samples were analysed to determine levels of urea and creatinine as proxy indicators of kidney function. Data revealed that pregnant women did not, on average, have a higher prevalence or intensity of infection of urinary schistosomiasis than non-pregnant women. During pregnancy, the level of prevalence and intensity of infection of S. haematobium was highest in the first trimester (0-13 weeks), dropped in the second trimester (14-26 weeks) and rose again in the third trimester (27-40 weeks). In addition, 24.8% of women were infected with hookworm, while none were diagnosed with malaria parasites. Of 250 samples analysed for serum urea and creatinine, none had significant levels of pathology, either in pregnant or non-pregnant women. Despite World Health Organization (WHO) recommendations that pregnant women should be treated with praziquantel after the first trimester, in practice this has not been the case in many countries, including Kenya. In view of this, healthcare providers should be informed to consider treatment of pregnant women infected with schistosomiasis during antenatal visits and whenever there is mass drug administration as recommended by the WHO.


Assuntos
Doenças Urogenitais Femininas/parasitologia , Complicações Parasitárias na Gravidez/parasitologia , Esquistossomose Urinária/parasitologia , Adolescente , Adulto , Animais , Estudos Transversais , Feminino , Doenças Urogenitais Femininas/epidemiologia , Humanos , Quênia/epidemiologia , Pessoa de Meia-Idade , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Schistosoma haematobium/isolamento & purificação , Schistosoma haematobium/fisiologia , Esquistossomose Urinária/epidemiologia , Adulto Jovem
6.
Curr HIV/AIDS Rep ; 11(3): 223-32, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24950732

RESUMO

An immune reconstitution disorder occurs in up to 40 % of severely immunodeficient HIV patients who commence antiretroviral therapy (ART), with an immune reconstitution inflammatory syndrome (IRIS) being encountered most commonly. Differences in the immunopathogenesis of an IRIS associated with different types of pathogen have become apparent but common features have also been defined. These include severe immunodeficiency prior to commencing ART associated with a high pathogen load and 'compensatory' immune responses, particularly innate immune responses, which inadequately control the pathogen and increase the risk of immunopathology as the immune system recovers on ART. Prevention of an IRIS may be achieved by optimising therapy for opportunistic infections before ART is commenced, delaying ART or using immunomodulatory therapy to prevent or suppress the immune response that causes the immunopathology. However, further clinical studies are required to examine these options in a systematic manner for the various types of IRIS.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Síndrome Inflamatória da Reconstituição Imune/prevenção & controle , Síndrome Inflamatória da Reconstituição Imune/terapia , Doenças Autoimunes , Criptococose/complicações , Humanos , Síndrome Inflamatória da Reconstituição Imune/etiologia , Tuberculose/complicações
7.
Phys Rev Lett ; 108(9): 091102, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22463623

RESUMO

Recently, there has been a tremendous increase in the number of identified extrasolar planetary systems. Our understanding of their formation is tied to exoplanet internal structure models, which rely upon equations of state of light elements and compounds such as water. Here, we present shock compression data for water with unprecedented accuracy that show that water equations of state commonly used in planetary modeling significantly overestimate the compressibility at conditions relevant to planetary interiors. Furthermore, we show that its behavior at these conditions, including reflectivity and isentropic response, is well-described by a recent first-principles based equation of state. These findings advocate that this water model be used as the standard for modeling Neptune, Uranus, and "hot Neptune" exoplanets and should improve our understanding of these types of planets.

8.
J Clin Microbiol ; 49(10): 3691-3, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21813723

RESUMO

We developed a real-time PCR to quantify 16S rRNA gene levels in plasma from HIV-infected patients as a marker of microbial translocation. The assay uses shrimp nuclease (SNuc) to eliminate DNA contamination, giving high sensitivity and low variability. The 16S rRNA gene levels measured in plasma from HIV patients correlated significantly with lipopolysaccharide levels.


Assuntos
Bacteriemia/diagnóstico , Translocação Bacteriana , Técnicas Bacteriológicas/métodos , Genes de RNAr , Infecções por HIV/complicações , Plasma/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , DNA Bacteriano/sangue , Humanos , Lipopolissacarídeos/sangue , Plasma/química , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Estatística como Assunto
9.
Anim Genet ; 42(3): 321-4, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21554349

RESUMO

We have constructed a genetic linkage map of the sheep X chromosome (OARX) containing 22 new gene loci from across the human X chromosome (HSAX). The female OARX linkage map has a total length of 152.6 cM with average gene spacing of 5.5 cM. Comparison with HSAX confirms one previously reported major breakpoint and inversion, and other minor rearrangements between OARX and HSAX. Comparison of the linkage map with sheep sequence data OAR 1.0 reveals a different arrangement of markers on the q arm, which may more accurately reflect the genuine arrangement of this region.


Assuntos
Alinhamento de Sequência , Carneiro Doméstico/genética , Cromossomo X/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , Cromossomos de Mamíferos/genética , Feminino , Ligação Genética , Marcadores Genéticos , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
10.
Osteoarthritis Cartilage ; 18(11): 1365-71, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20708004

RESUMO

OBJECTIVE: To evaluate subjective sleep quality and its relationship to fatigue in older adults with osteoarthritis (OA). METHOD: In a community cohort with hip/knee OA, subjective sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) and fatigue was measured by the Profile of Mood States - Fatigue subscale (POMS-F). Correlates of sleep quality and fatigue were determined by standardized interviews including socio-demographics, OA severity (Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) summary score), comorbidity, depression (Center for Epidemiologic Studies Depression Scale, CES-D), stressful life events, daytime napping, symptoms of restless legs syndrome (RLS) and prior sleep disorder diagnoses. Logistic regression examined correlates of poor sleep (PSQI score>5). Linear regression evaluated the relationship between poor sleep and fatigue, and the effect of napping on this relationship. RESULTS: In 613 respondents, mean age was 78 years, 78% were female, 11% had concomitant fibromyalgia, and 26% had 3+ comorbid conditions. Responses indicated moderate OA severity. Seventy percent reported poor sleep; 25% met criteria for RLS and 6.5% reported a diagnosed sleep disorder. Independent correlates of poor sleep were: greater arthritis severity (adjusted odds ratio (OR) per unit increase in WOMAC score=1.03, P<0.0001), 3+ comorbid conditions (adjusted OR=1.88; P=0.03), depressed mood (adjusted OR per unit increase in CES-D score=1.09, P<0.0001), and RLS (adjusted OR=1.87; P=0.02). Controlling for previously reported fatigue correlates, poor sleep was significantly associated with greater fatigue (parameter estimate=1.63, P=0.0003) and napping did not moderate this relationship (P=0.55 for the interaction between napping and poor sleep). CONCLUSIONS: Among older people with OA, poor sleep is highly prevalent and significantly linked with fatigue. Identifying the nature of sleep disturbances in OA is important as treatment of sleep disturbances may reduce OA-related fatigue.


Assuntos
Fadiga/epidemiologia , Osteoartrite do Quadril/complicações , Osteoartrite do Joelho/complicações , Transtornos do Sono-Vigília/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Fadiga/etiologia , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Dor/complicações , Índice de Gravidade de Doença , Transtornos do Sono-Vigília/etiologia
11.
Diabetologia ; 52(8): 1628-37, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19536518

RESUMO

AIMS/HYPOTHESIS: It is recommended that patients with diabetes reduce their intake of saturated fat and increase their intake of monounsaturated fat or carbohydrate. However, high-carbohydrate diets may result in higher saturated fatty acids in VLDL-triacylglycerol. This is attributed to de novo lipogenesis, although synthesis of specific fatty acids is rarely measured. The objective of this study was to examine the contribution of de novo fatty acid synthesis to VLDL-triacylglycerol composition. It was hypothesised that levels of total and de novo synthesised fatty acids would increase with increased carbohydrate intake in diabetic participants. METHODS: Seven individuals with type 2 diabetes mellitus and seven matched non-diabetic controls consumed two diets differing in fat energy (lower fat <25%, higher fat >35%) for 3 days in a randomised crossover design. Blood samples were drawn before and 24 h after the ingestion of (2)H-labelled water. RESULTS: In the control participants, the higher-fat diet resulted in a 40% reduction in VLDL-triacylglycerol fatty acids because of decreases in myristic, palmitic, palmitoleic and linoleic acids, but the opposite trend occurred in participants with diabetes. The lower-fat diet increased the fractional synthesis rate by 35% and 25% in the control and diabetes participants, respectively (range: 0-33%). Palmitate accounted for 71% of fatty acids synthesised (range: 44-84% total de novo synthesised fatty acids). CONCLUSIONS/INTERPRETATION: (2)H incorporation was used for the first time in humans showing variability in the synthesis rate of specific fatty acids, even palmitic acid. A lower-fat diet stimulated saturated fatty acid synthesis at high rates, but no net stimulation of synthesis of any fatty acid occurred in the diabetes group. The implications of this finding for our understanding of lipid metabolism in diabetes require further investigation.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Ácidos Graxos/biossíntese , Lipoproteínas VLDL/sangue , Lipoproteínas VLDL/química , Triglicerídeos/sangue , Triglicerídeos/química , Adulto , Apolipoproteínas E/genética , Índice de Massa Corporal , Gorduras na Dieta , Feminino , Genótipo , Hemoglobinas Glicadas/metabolismo , Humanos , Lipoproteínas VLDL/biossíntese , Masculino , Pessoa de Meia-Idade , Valores de Referência , Triglicerídeos/biossíntese
12.
J Cell Biol ; 145(5): 1103-15, 1999 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-10352025

RESUMO

Expression of the basement membrane heparan sulfate proteoglycan (HSPG), perlecan (Pln), mRNA, and protein has been examined during murine development. Both Pln mRNA and protein are highly expressed in cartilaginous regions of developing mouse embryos, but not in areas of membranous bone formation. Initially detected at low levels in precartilaginous areas of d 12.5 embryos, Pln protein accumulates in these regions through d 15.5 at which time high levels are detected in the cartilage primordia. Laminin and collagen type IV, other basal lamina proteins commonly found colocalized with Pln, are absent from the cartilage primordia. Accumulation of Pln mRNA, detected by in situ hybridization, was increased in d 14.5 embryos. Cartilage primordia expression decreased to levels similar to that of the surrounding tissue at d 15.5. Pln accumulation in developing cartilage is preceded by that of collagen type II. To gain insight into Pln function in chondrogenesis, an assay was developed to assess the potential inductive activity of Pln using multipotential 10T1/2 murine embryonic fibroblast cells. Culture on Pln, but not on a variety of other matrices, stimulated extensive formation of dense nodules reminiscent of embryonic cartilaginous condensations. These nodules stained intensely with Alcian blue and collagen type II antibodies. mRNA encoding chondrocyte markers including collagen type II, aggrecan, and Pln was elevated in 10T1/2 cells cultured on Pln. Human chondrocytes that otherwise rapidly dedifferentiate during in vitro culture also formed nodules and expressed high levels of chondrocytic marker proteins when cultured on Pln. Collectively, these studies demonstrate that Pln is not only a marker of chondrogenesis, but also strongly potentiates chondrogenic differentiation in vitro.


Assuntos
Condrócitos/metabolismo , Desenvolvimento Embrionário e Fetal , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/biossíntese , Proteoglicanas/biossíntese , Animais , Biomarcadores , Diferenciação Celular , Condrócitos/citologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , RNA Mensageiro/análise , RNA Mensageiro/biossíntese
13.
Science ; 166(3910): 1278-80, 1969 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-5350321

RESUMO

Feeding sublethal amounts of p,p'-DDT to pigeons caused an increase in thyroid weight and a reduction in colloid content of the follicles. This may reflect a hyper- or hypo-functioning gland and may be cotnnected with recent reductions in egg shell weights in wild birds. The effect was accompanied by increased liver weight.


Assuntos
DDT/farmacologia , Tamanho do Órgão , Glândula Tireoide/efeitos dos fármacos , Ração Animal , Animais , Encéfalo/efeitos dos fármacos , Coloides , Columbidae , Fígado/efeitos dos fármacos
14.
Science ; 165(3896): 914-6, 1969 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-5798316

RESUMO

The O,p'-DDT in technical DDT is broken down to p,p'-DDT and then to 1,1-dichloro- 2,2-bis(p-chlorophenyl)ethylene in living avian tissue. In the anaerobic conditions existing after death, O,p'-DDT is metabolized to 1,1-dichloro-2-(O-chlorophenyl)-2-(p-chlorophenyl)ethane. The absence of O,p'-DDT and metabolites in field specimens is ascribed to the rapid rate of breakdown and a masking of the 1,1-dichloro-2-(O-chlorophenyl)-2-(p-chlorophenyl)ethane residue during analysis by the relatively large amounts of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene.


Assuntos
Columbidae , DDT/metabolismo , Oxigênio , Tecido Adiposo/metabolismo , Animais , DDT/análise , Morte , Técnicas In Vitro , Fígado/metabolismo , Músculos/metabolismo , Estereoisomerismo , Fatores de Tempo
15.
J Phys Condens Matter ; 21(1): 015502, 2009 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21817223

RESUMO

The band structure of Cu(2)O is calculated using density functional theory in the generalized gradient approximation. By taking spin-orbit coupling into account the split between the Γ(7)(+) and the Γ(8)(+) valence band states is obtained as 128 meV. The highest valence band shows a noticeable nonparabolicity close to the Γ point. This is important for the quantitative description of excitons in this material, which is considered to be the best candidate for the confirmation that Bose-Einstein condensation also occurs in excitonic systems.

16.
Phys Rev E ; 99(4-2): 047201, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31108609

RESUMO

Dharma-wardana et al. [M. W. C. Dharma-wardana et al., Phys. Rev. E 96, 053206 (2017)2470-004510.1103/PhysRevE.96.053206] recently calculated dynamic electrical conductivities for warm dense matter as well as for nonequilibrium two-temperature states termed "ultrafast matter" (UFM) [M. W. C. Dharma-wardana, Phys. Rev. E 93, 063205 (2016)2470-004510.1103/PhysRevE.93.063205]. In this Comment we present two evident reasons why these UFM calculations are neither suited to calculate dynamic conductivities nor x-ray Thomson scattering spectra in isochorically heated warm dense aluminum. First, the ion-ion structure factor, a major input into the conductivity and scattering spectra calculations, deviates strongly from that of isochorically heated aluminum. Second, the dynamic conductivity does not show a non-Drude behavior which is an essential prerequisite for a correct description of the absorption behavior in aluminum. Additionally, we clarify misinterpretations by Dharma-wardana et al. concerning the conductivity measurements of Gathers [G. R. Gathers, Int. J. Thermophys. 4, 209 (1983)IJTHDY0195-928X10.1007/BF00502353].

17.
Sci Rep ; 9(1): 10155, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300690

RESUMO

Water, methane, and ammonia are commonly considered to be the key components of the interiors of Uranus and Neptune. Modelling the planets' internal structure, evolution, and dynamo heavily relies on the properties of the complex mixtures with uncertain exact composition in their deep interiors. Therefore, characterising icy mixtures with varying composition at planetary conditions of several hundred gigapascal and a few thousand Kelvin is crucial to improve our understanding of the ice giants. In this work, pure water, a water-ethanol mixture, and a water-ethanol-ammonia "synthetic planetary mixture" (SPM) have been compressed through laser-driven decaying shocks along their principal Hugoniot curves up to 270, 280, and 260 GPa, respectively. Measured temperatures spanned from 4000 to 25000 K, just above the coldest predicted adiabatic Uranus and Neptune profiles (3000-4000 K) but more similar to those predicted by more recent models including a thermal boundary layer (7000-14000 K). The experiments were performed at the GEKKO XII and LULI2000 laser facilities using standard optical diagnostics (Doppler velocimetry and optical pyrometry) to measure the thermodynamic state and the shock-front reflectivity at two different wavelengths. The results show that water and the mixtures undergo a similar compression path under single shock loading in agreement with Density Functional Theory Molecular Dynamics (DFT-MD) calculations using the Linear Mixing Approximation (LMA). On the contrary, their shock-front reflectivities behave differently by what concerns both the onset pressures and the saturation values, with possible impact on planetary dynamos.

18.
Mol Genet Metab Rep ; 18: 39-44, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30705824

RESUMO

BACKGROUND: In phenylketonuria (PKU), weaning is considered more challenging when compared to feeding healthy infants. The primary aim of weaning is to gradually replace natural protein from breast milk or standard infant formula with solids containing equivalent phenylalanine (Phe). In addition, a Phe-free second stage L-amino acid supplement is usually recommended from around 6 months to replace Phe-free infant formula. Our aim was to assess different weaning approaches used by health professionals across Europe. METHODS: A cross sectional questionnaire (survey monkey®) composed of 31 multiple and single choice questions was sent to European colleagues caring for inherited metabolic disorders (IMD). Centres were grouped into geographical regions for analysis. RESULTS: Weaning started at 17-26 weeks in 85% (n = 81/95) of centres, >26 weeks in 12% (n = 11/95) and < 17 weeks in 3% (n = 3/95). Infant's showing an interest in solid foods, and their age, were important determinant factors influencing weaning commencement. 51% (n = 48/95) of centres introduced Phe containing foods at 17-26 weeks and 48% (n = 46/95) at >26 weeks. First solids were mainly low Phe vegetables (59%, n = 56/95) and fruit (34%, n = 32/95).A Phe exchange system to allocate dietary Phe was used by 52% (n = 49/95) of centres predominantly from Northern and Southern Europe and 48% (n = 46/95) calculated most Phe containing food sources (all centres in Eastern Europe and the majority from Germany and Austria). Some centres used a combination of both methods.A second stage Phe-free L-amino acid supplement containing a higher protein equivalent was introduced by 41% (n = 39/95) of centres at infant age 26-36 weeks (mainly from Germany, Austria, Northern and Eastern Europe) and 37% (n = 35/95) at infant age > 1y mainly from Southern Europe. 53% (n = 50/95) of centres recommended a second stage Phe-free L-amino acid supplement in a spoonable or semi-solid form. CONCLUSIONS: Weaning strategies vary throughout European PKU centres. There is evidence to suggest that different infant weaning strategies may influence longer term adherence to the PKU diet or acceptance of Phe-free L-amino acid supplements; rendering prospective long-term studies important. It is essential to identify an effective weaning strategy that reduces caregiver burden but is associated with acceptable dietary adherence and optimal infant feeding development.

19.
Parasitology ; 135(12): 1447-55, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18775092

RESUMO

Soil-transmitted helminthiasis (STH) is a scourge to the health and well-being of infants and pre-schoolchildren throughout many parts of sub-Saharan Africa. To improve maternal and child health, regular de-worming is recommended and often delivered from mother and child health (MCH) clinics, yet there have been few studies monitoring the progress and impact of interventions on local levels of disease. A cross-sectional parasitological survey, supplemented with questionnaires, was therefore conducted across 10 Ungujan villages examining mothers (n=322) and their pre-school children (n=359). Within children, mean prevalence of ascariasis, trichuriasis and hookworm was 8.6% (95% CI 5.5-11.8), 18.9% (95% CI 14.5-23.4) and 1.7% (95% CI 0.2-3.5) while in mothers mean prevalence was 6.7% (95% CI 3.7-9.7), 11.9% (95% CI 8.0-15.8) and 1.9% (95% CI 0.2-3.5), respectively. There was, however, significant spatial heterogeneity of STH by village, 2 villages having much elevated levels of infection, although general access to anthelminthics and utilization of village MCH clinics was good. Levels of parasite aggregation (k) were determined and a multilevel logistic regression model identified access to a household latrine [OR=0.56 (95% CI 0.32-0.99)] and having an infected household member [OR=3.72 (95% CI 2.22-6.26)] as observed risk factors. To further investigate worm burdens of Ascaris lumbricoides, adult worms were expelled using Combantrin and measured. A negative relationship between mean worm burden and mean worm mass was found. Villages in the north of Unguja represent locations where there is elevated prevalence of both ascariasis and trichuriasis and it appears that local factors are particularly favourable for transmission of these helminths. From a perspective of control, in such locations, intervention efforts should be stepped up and greater efforts placed upon improving household sanitation.


Assuntos
Ascaríase/epidemiologia , Solo/parasitologia , Adulto , Pré-Escolar , Estudos Transversais , Coleta de Dados , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Inquéritos e Questionários , Tanzânia
20.
Mol Genet Metab Rep ; 16: 82-89, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30101073

RESUMO

BACKGROUND: In infants with phenylketonuria (PKU), dietary management is based on lowering and titrating phenylalanine (Phe) intake from breast milk or standard infant formula in combination with a Phe-free infant formula in order to maintain blood Phe levels within target range. Professionals use different methods to feed infants with PKU and our survey aimed to document practices across Europe. METHODS: We sent a cross sectional, survey monkey® questionnaire to European health professionals working in IMD. It contained 31 open and multiple-choice questions. The results were analysed according to different geographical regions. RESULTS: Ninety-five centres from 21 countries responded. Over 60% of centres commenced diet in infants by age 10 days, with 58% of centres implementing newborn screening by day 3 post birth. At diagnosis, infant hospital admission occurred in 61% of metabolic centres, mainly in Eastern, Western and Southern Europe. Breastfeeding fell sharply following diagnosis with only 30% of women still breast feeding at 6 months.53% of centres gave pre-measured Phe-free infant formula before each breast feed and 23% alternated breast feeds with Phe-free infant formula. With standard infant formula feeds, measured amounts were followed by Phe-free infant formula to satiety in 37% of centres (n = 35/95), whereas 44% (n = 42/95) advised mixing both formulas together. Weaning commenced between 17 and 26 weeks in 85% centres, ≥26 weeks in 12% and < 17 weeks in 3%. DISCUSSION: This is the largest European survey completed on PKU infant feeding practices. It is evident that practices varied widely across Europe, and the practicalities of infant feeding in PKU received little focus in the PKU European Guidelines (2017). There are few reports comparing different feeding techniques with blood Phe control, Phe fluctuations and growth. Controlled prospective studies are necessary to assess how different infant feeding practices may influence longer term feeding development.

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