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1.
Nature ; 596(7870): 80-86, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349288

RESUMO

Flooding affects more people than any other environmental hazard and hinders sustainable development1,2. Investing in flood adaptation strategies may reduce the loss of life and livelihood caused by floods3. Where and how floods occur and who is exposed are changing as a result of rapid urbanization4, flood mitigation infrastructure5 and increasing settlements in floodplains6. Previous estimates of the global flood-exposed population have been limited by a lack of observational data, relying instead on models, which have high uncertainty3,7-11. Here we use daily satellite imagery at 250-metre resolution to estimate flood extent and population exposure for 913 large flood events from 2000 to 2018. We determine a total inundation area of 2.23 million square kilometres, with 255-290 million people directly affected by floods. We estimate that the total population in locations with satellite-observed inundation grew by 58-86 million from 2000 to 2015. This represents an increase of 20 to 24 per cent in the proportion of the global population exposed to floods, ten times higher than previous estimates7. Climate change projections for 2030 indicate that the proportion of the population exposed to floods will increase further. The high spatial and temporal resolution of the satellite observations will improve our understanding of where floods are changing and how best to adapt. The global flood database generated from these observations will help to improve vulnerability assessments, the accuracy of global and local flood models, the efficacy of adaptation interventions and our understanding of the interactions between landcover change, climate and floods.


Assuntos
Aclimatação , Demografia , Planejamento em Desastres , Inundações/estatística & dados numéricos , Modelos Teóricos , Imagens de Satélites , Bases de Dados como Assunto , Clima Extremo , Humanos , Medição de Risco
2.
Phys Rev Lett ; 127(10): 100405, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34533334

RESUMO

We present an experimental study of a two component Fermi gas following an interaction quench into the superfluid phase. Starting with a weakly attractive gas in the normal phase, interactions are ramped to unitarity at a range of rates and we measure the subsequent dynamics as the gas approaches equilibrium. Both the formation and condensation of fermion pairs are mapped via measurements of the pair momentum distribution and can take place on very different timescales, depending on the adiabaticity of the quench. The contact parameter is seen to respond very quickly to changes in the interaction strength, indicating that short-range correlations, based on the occupation of high-momentum modes, evolve far more rapidly than the correlations in low-momentum modes necessary for pair condensation.

3.
Int Arch Occup Environ Health ; 94(6): 1191-1199, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34023963

RESUMO

OBJECTIVES: To evaluate whether there is an increased risk for noise-induced hearing loss at high altitude rsp. in hypobaric hypoxia. METHODS: Thirteen volunteers got standard audiometry at 125, 250, 500, 750, 1000, 1500, 2000, 3000, 4000, 6000, and 8000 Hz before and after 10 min of white noise at 90 dB. The system was calibrated for the respective altitude. Measurements were performed at Kathmandu (1400 m) and at Gorak Shep (5300 m) (Solo Khumbu/Nepal) after 10 days of acclimatization while on trek. Temporary threshold shift (TTS) was analyzed by descriptive statistics and by factor analysis. RESULTS: TTS is significantly more pronounced at high altitudes. Acclimatization does not provide any protection of the inner ear, although it increases arterial oxygen saturation. CONCLUSION: The thresholds beyond which noise protection is recommended (> 80 dB) or necessary (> 85 dB) are not sufficient at high altitudes. We suggest providing protective devices above an altitude of 1500 m ("ear threshold altitude") when noise level is higher than 75 dB and using them definitively above 80 dB. This takes the individual reaction on hypobaric hypoxia at high altitude into account.


Assuntos
Altitude , Limiar Auditivo , Exposição Ambiental/efeitos adversos , Ruído/efeitos adversos , Oxigênio , Aclimatação , Adulto , Audiometria , Expedições , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Phys Rev Lett ; 124(15): 150401, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32357063

RESUMO

We present an experimental and theoretical study of the phonon mode in a unitary Fermi gas. Using two-photon Bragg spectroscopy, we measure excitation spectra at a momentum of approximately half the Fermi momentum, both above and below the superfluid critical temperature T_{c}. Below T_{c}, the dominant excitation is the Bogoliubov-Anderson (BA) phonon mode, driven by gradients in the phase of the superfluid order parameter. The temperature dependence of the BA phonon is consistent with a theoretical model based on the quasiparticle random phase approximation in which the dominant damping mechanism is via collisions with thermally excited quasiparticles. As the temperature is increased above T_{c}, the phonon evolves into a strongly damped collisional mode, accompanied by an abrupt increase in spectral width. Our study reveals strong similarities between sound propagation in the unitary Fermi gas and bosonic liquid helium.

5.
BMC Vet Res ; 16(1): 33, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005239

RESUMO

BACKGROUND: In dairy herds, mastitis causes detrimental economic losses. Genetic selection offers a sustainable tool to select animals with reduced susceptibility towards postpartum diseases. Studying underlying mechanisms is important to assess the physiological processes that cause differences between selected haplotypes. Therefore, the objective of this study was to establish an in vivo infection model to study the impact of selecting for alternative paternal haplotypes in a particular genomic region on cattle chromosome 18 for mastitis susceptibility under defined conditions in uniparous dairy cows. RESULTS: At the start of pathogen challenge, no significant differences between the favorable (Q) and unfavorable (q) haplotypes were detected. Intramammary infection (IMI) with Staphylococcus aureus 1027 (S. aureus, n = 24, 96 h) or Escherichia coli 1303 (E. coli, n = 12, 24 h) was successfully induced in all uniparous cows. This finding was confirmed by clinical signs of mastitis and repeated recovery of the respective pathogen from milk samples of challenged quarters in each animal. After S. aureus challenge, Q-uniparous cows showed lower somatic cell counts 24 h and 36 h after challenge (P < 0.05), lower bacterial shedding in milk 12 h after challenge (P < 0.01) and a minor decrease in total milk yield 12 h and 24 h after challenge (P < 0.01) compared to q-uniparous cows. CONCLUSION: An in vivo infection model to study the impact of genetic selection for mastitis susceptibility under defined conditions in uniparous dairy cows was successfully established and revealed significant differences between the two genetically selected haplotype groups. This result might explain their differences in susceptibility towards IMI. These clinical findings form the basis for further in-depth molecular analysis to clarify the underlying genetic mechanisms for mastitis resistance.


Assuntos
Mastite Bovina/genética , Mastite Bovina/microbiologia , Herança Paterna , Animais , Bovinos , Indústria de Laticínios , Escherichia coli , Infecções por Escherichia coli/veterinária , Feminino , Haplótipos , Masculino , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus
6.
J Dairy Sci ; 103(7): 6364-6373, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32307160

RESUMO

Infection and inflammation of the mammary gland, and especially prevention of mastitis, are still major challenges for the dairy industry. Different approaches have been tried to reduce the incidence of mastitis. Genetic selection of cows with lower susceptibility to mastitis promises sustainable success in this regard. Bos taurus autosome (BTA) 18, particularly the region between 43 and 59 Mb, harbors quantitative trait loci (QTL) for somatic cell score, a surrogate trait for mastitis susceptibility. Scrutinizing the molecular bases hereof, we challenged udders from half-sib heifers having inherited either favorable paternal haplotypes for somatic cell score (Q) or unfavorable haplotypes (q) with the Staphylococcus aureus pathogen. RNA sequencing was used for an in-depth analysis of challenge-related alterations in the hepatic transcriptome. Liver exerts highly relevant immune functions aside from being the key metabolic organ. Hence, a holistic approach focusing on the liver enabled us to identify challenge-related and genotype-dependent differentially expressed genes and underlying regulatory networks. In response to the S. aureus challenge, we found that heifers with Q haplotypes displayed more activated immune genes and pathways after S. aureus challenge compared with their q half-sibs. Furthermore, we found a significant enrichment of differentially expressed loci in the genomic target region on BTA18, suggesting the existence of a regionally acting regulatory element with effects on a variety of genes in this region.


Assuntos
Predisposição Genética para Doença , Fígado/metabolismo , Mastite Bovina/imunologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus , Transcriptoma , Animais , Bovinos , Indústria de Laticínios , Suscetibilidade a Doenças/veterinária , Feminino , Haplótipos , Glândulas Mamárias Animais/metabolismo , Mastite Bovina/genética , Fenótipo , Locos de Características Quantitativas , Seleção Genética , Análise de Sequência de RNA , Infecções Estafilocócicas/genética , Staphylococcus aureus/genética , Vacinação/veterinária
7.
Phys Rev Lett ; 122(20): 203401, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31172752

RESUMO

We present an experimental study of the high-energy excitation spectra of unitary Fermi gases. Using focused beam Bragg spectroscopy, we locally probe atoms in the central region of a harmonically trapped cloud where the density is nearly uniform, enabling measurements of the dynamic structure factor for a range of temperatures both below and above the superfluid transition. Applying sum rules to the measured Bragg spectra, we resolve the characteristic behavior of the universal contact parameter, C, across the superfluid transition. We also employ a recent theoretical result for the kinetic (second-moment) sum rule to obtain the internal energy of gases at unitarity.

8.
BMC Vet Res ; 15(1): 285, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395056

RESUMO

The original article [1] contained an error whereby the captions to Figs 2 and 3 were mistakenly inverted; this has now been corrected.

9.
BMC Vet Res ; 15(1): 241, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296208

RESUMO

BACKGROUND: A major challenge in modern medicine and animal husbandry is the issue of antimicrobial resistance. One approach to solving this potential medical hazard is the selection of farm animals with less susceptibility to infectious diseases. Recent advances in functional genome analysis and quantitative genetics have opened the horizon to apply genetic marker information for efficiently identifying animals with preferential predisposition regarding health traits. The current study characterizes functional traits with a focus on udder health in dairy heifers. The animals were selected for having inherited alternative paternal haplotypes for a genomic region on Bos taurus chromosome (BTA) 18 genetically associated with divergent susceptibility to longevity and animal health, particularly mastitis. RESULTS: In the first weeks of lactation, the q heifers which had inherited the unfavorable (q) paternal haplotype displayed a significantly higher number of udder quarters with very low somatic cell count (< 10,000 cells / ml) compared to their paternal half-sib sisters with the favorable (Q) paternal haplotype. This might result in impaired mammary gland sentinel function towards invading pathogens. Furthermore, across the course of the first lactation, there was indication that q half-sib heifers showed higher somatic cell counts, a surrogate trait for udder health, in whole milkings compared to their paternal half-sib sisters with the favorable (Q) paternal haplotype. Moreover, heifers with the haplotype Q had a higher feed intake and higher milk yield compared to those with the q haplotype. Results of this study indicate that differences in milk production and calculated energy balance per se are not the main drivers of the genetically determined differences between the BTA18 Q and q groups of heifers. CONCLUSIONS: The paternally inherited haplotype from a targeted BTA18 genomic region affect somatic cell count in udder quarters during the early postpartum period and might also contribute to further aspects of animal's health and performance traits due to indirect effects on feed intake and metabolism.


Assuntos
Glândulas Mamárias Animais/fisiologia , Herança Paterna , Animais , Bovinos , Mapeamento Cromossômico , Ingestão de Alimentos/genética , Metabolismo Energético/genética , Feminino , Haplótipos/genética , Lactação/genética , Masculino , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/genética , Período Pós-Parto
10.
Am J Transplant ; 18(5): 1275-1277, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29314647

RESUMO

Scarcity of donors leads transplant surgeons to consider extended-criteria lungs and occasionally to accept the unlikely. Here we report a case of successful single lung transplantation from a donor 8 months after double lung transplantation.


Assuntos
Morte Encefálica , Pneumopatias/cirurgia , Transplante de Pulmão/métodos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Transplantados , Resultado do Tratamento
11.
Phys Rev Lett ; 118(21): 219903, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28598666

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.113.013002.

12.
Herz ; 42(1): 27-44, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28127638

RESUMO

Cardiogenic shock is an acute emergency, which is classically managed by medical support with inotropes or vasopressors and frequently requires invasive ventilation. However, both catecholamines and ventilation are associated with a worse prognosis, and many patients deteriorate despite all efforts. Mechanical circulatory support is increasingly considered to allow for recovery or to bridge until making a decision or definite treatment. Of all devices, extracorporeal membrane oxygenation (ECMO) is the most widely used. Here we review features and strategical considerations for the use of ECMO in cardiogenic shock and cardiac arrest.


Assuntos
Cuidados Críticos/métodos , Oxigenação por Membrana Extracorpórea/instrumentação , Parada Cardíaca/diagnóstico , Parada Cardíaca/terapia , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/terapia , Desenho de Equipamento , Medicina Baseada em Evidências , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Resultado do Tratamento
13.
Am J Transplant ; 16(5): 1579-87, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26607844

RESUMO

This single-center study examines the incidence, etiology, and outcomes associated with prolonged mechanical ventilation (PMV), defined as time to definite spontaneous ventilation >21 days after double lung transplantation (LTx). A total of 690 LTx recipients between January 2005 and December 2012 were analyzed. PMV was necessary in 95 (13.8%) patients with decreasing incidence during the observation period (p < 0.001). Independent predictors of PMV were renal replacement therapy (odds ratio [OR] 11.13 [95% CI, 5.82-21.29], p < 0.001), anastomotic dehiscence (OR 8.74 [95% CI 2.42-31.58], p = 0.001), autoimmune comorbidity (OR 5.52 [95% CI 1.86-16.41], p = 0.002), and postoperative neurologic complications (OR 5.03 [95% CI 1.98-12.81], p = 0.001), among others. Overall 1-year survival was 86.0% (90.4% for LTx between 2010 and 2012); it was 60.7% after PMV and 90.0% in controls (p < 0.001). Conditional long-term outcome among hospital survivors, however, did not differ between the groups (p = 0.78). Multivariate analysis identified renal replacement therapy (hazard ratio [HR] 3.55 [95% CI 2.40-5.25], p < 0.001), post-LTx extracorporeal membrane oxygenation (HR 3.47 [95% CI 2.06-5.83], p < 0.001), and prolonged inotropic support (HR 1.95 [95% CI 1.39-2.75], p < 0.001), among others, as independent predictors of mortality. In conclusion, PMV complicated 14% of LTx procedures and, although associated with increased in-hospital mortality, outcomes among patients surviving to hospital discharge were unaffected.


Assuntos
Oxigenação por Membrana Extracorpórea/mortalidade , Pneumopatias/mortalidade , Transplante de Pulmão/efeitos adversos , Complicações Pós-Operatórias/mortalidade , Respiração Artificial/mortalidade , Adolescente , Adulto , Criança , Feminino , Seguimentos , Alemanha/epidemiologia , Mortalidade Hospitalar/tendências , Humanos , Incidência , Pneumopatias/complicações , Pneumopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo
14.
Opt Lett ; 41(11): 2505-8, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27244400

RESUMO

Resonant frequency modulation imaging is used to detect free falling ultra-cold atoms. A theoretical comparison of fluorescence imaging (FI) and frequency modulation imaging (FMI) is made, indicating that for low optical depth clouds, FMI accomplished a higher signal-to-noise ratio under conditions necessary for a 200 µm spatially resolved atom interferometer. A 750 ms time-of-flight measurement reveals near atom shot-noise limited number measurements of 2×106 Bose-condensed Rb87 atoms. The detection system is applied to high precision spinor BEC based atom interferometer.

15.
Opt Lett ; 41(20): 4795-4798, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28005895

RESUMO

An imaging system is presented that is capable of far-detuned non-destructive imaging of a Bose-Einstein condensate with the signal proportional to the second spatial derivative of the density. Whilst demonstrated with application to Rb85, the technique generalizes to other atomic species and is shown to be capable of a signal-to-noise of ∼25 at 1 GHz detuning with 100 in-trap images showing no observable heating or atom loss. The technique is also applied to the observation of individual trajectories of stochastic dynamics inaccessible to single shot imaging. Coupled with a fast optical phase locked loop, the system is capable of dynamically switching to resonant absorption imaging during the experiment.

16.
Phys Rev Lett ; 117(13): 138501, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27715130

RESUMO

A Bose-Einstein condensate is used as an atomic source for a high precision sensor. A 5×10^{6} atom F=1 spinor condensate of ^{87}Rb is released into free fall for up to 750 ms and probed with a T=130 ms Mach-Zehnder atom interferometer based on Bragg transitions. The Bragg interferometer simultaneously addresses the three magnetic states |m_{f}=1,0,-1⟩, facilitating a simultaneous measurement of the acceleration due to gravity with a 1000 run precision of Δg/g=1.45×10^{-9} and the magnetic field gradient to a precision of 120 pT/m.

17.
Oecologia ; 182(4): 995-1005, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27651228

RESUMO

Intraspecific variability is increasingly recognized as an important component of foraging behavior that can have implications for both population and community dynamics. We used an individual-level approach to describe the foraging behavior of an abundant, generalist predator that inhabits a dynamic marine ecosystem, focusing specifically on the different foraging strategies used by individuals in the same demographic group. We collected data on movements and diving behavior of adult female California sea lions (Zalophus californianus) across multiple foraging trips to sea. Sea lions (n = 35) used one of three foraging strategies that primarily differed in their oceanic zone and dive depth: a shallow, epipelagic strategy, a mixed epipelagic/benthic strategy, and a deep-diving strategy. Individuals varied in their degree of fidelity to a given strategy, with 66 % of sea lions using only one strategy on all or most of their foraging trips across the two-month tracking period. All foraging strategies were present in each of the sampling years, but there were inter-annual differences in the population-level importance of each strategy that may reflect changes in prey availability. Deep-diving sea lions traveled shorter distances and spent a greater proportion of time at the rookery than sea lions using the other two strategies, which may have energetic and reproductive implications. These results highlight the importance of an individual-based approach in describing the foraging behavior of female California sea lions and understanding how they respond to the seasonal and annual changes in prey availability that characterize the California Current System.


Assuntos
Comportamento Alimentar , Leões-Marinhos , Animais , Mergulho , Ecossistema , Meio Ambiente
18.
Z Rheumatol ; 75(10): 999-1005, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-27535273

RESUMO

The aim of the rheumatology network ADAPTHERA ("risk-adapted rheumatology therapy") is to achieve a comprehensive improvement in rheumatology care by coordinating treatment in a regional, trans-sectoral network. Accompanying biomedical research projects, training concepts, and the construction of a rheumatology register (gathering data and biomaterials) should furthermore ensure the stable and sustainable optimisation of care. In the pilot phase (2012-2015) the focus of the ADAPTHERA network, required as a "regional key project" within the framework of the Initiative on Health Economy of Rheinland-Palatinate (RL-P), Germany, was placed on the optimisation of the early diagnosis of rheumatoid arthritis, where it is well-known that there is a significant care deficit.Through the intensive, stable, and coordinated cooperation of all health care partners in the field of rheumatology (registered general practitioners and orthopaedic specialists, registered core rheumatologists as well as the Association of Rheumatology of RL-P) a unique regional, comprehensive offer with verifiable care optimisation has been established in RL-P. The network is supported by outstanding collaboration with the Association of Statutory Health Insurance Physicians and the self-help organisation Rheumatology League.The aims that were established at the start of the project will be achieved by the end of the pilot phase:- significant improvement in the early diagnosis of rheumatoid arthritis (an average of 23.7 days until diagnosis by rheumatologists)- access covering all health insurance (regardless of the particular scheme the patients belong to)- comprehensive (verifiable participation of general practitioners from all over RL-P)- data and biomaterials collection, established as a basis for biomarker research, and a rheumatology register for RL-P.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Programas Nacionais de Saúde/organização & administração , Programas Médicos Regionais/organização & administração , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/terapia , Reumatologia/organização & administração , Atenção à Saúde/organização & administração , Humanos , Modelos Organizacionais , Sistema de Registros
19.
Internist (Berl) ; 57(9): 856-63, 2016 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-27411792

RESUMO

Extracorporeal membrane oxygenation (ECMO) is a special form of a miniaturized heart-lung machine with the ultimate goal to stabilize critically ill patients. Dependent on the cannulation strategy ECMO can support or replace heart and/or lung function. Medical indications and contraindications have to be evaluated thoroughly before cannulation. Moreover, before ECMO initiation a solid treatment aim has to be defined: bridge to recovery, bridge to decision, bridge to transplantation, and bridge to destination (i. e. implantation of a permanent assist device). Regarding invasiveness of the system, potential life-threatening complications, requirement of standardized monitoring of the patient and the device as well as tertiary care infrastructure, ECMO should exclusively be used in highly experienced tertiary centers.


Assuntos
Estado Terminal/terapia , Procedimentos Clínicos/organização & administração , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/tendências , Medicina Baseada em Evidências , Humanos , Seleção de Pacientes , Resultado do Tratamento
20.
Int J Neuropsychopharmacol ; 18(10): pyv050, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25991656

RESUMO

The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research.


Assuntos
Função Executiva/fisiologia , Objetivos , Hábitos , Desempenho Psicomotor/fisiologia , Serotonina/metabolismo , Animais , Humanos , Modelos Neurológicos , Modelos Psicológicos
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