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1.
Oecologia ; 201(3): 853-861, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36773071

RESUMO

Animals often respond to climate change with changes in morphology, e.g., shrinking body size with increasing temperatures, as expected by Bergmann's rule. Because small body size can have fitness costs for individuals, this trend could threaten populations. Recent studies, however, show that morphological responses to climate change and the resulting fitness consequences cannot be generalized even among related species. In this long-term study, we investigate the interaction between ambient temperature, body size and survival probability in a large number of individually marked wild adult female Natterer's bats (Myotis nattereri). We compare populations from two geographical regions in Germany with a different climate. In a sliding window analysis, we found larger body sizes in adult females that were raised in warmer summers only in the northern population, but not in the southern population that experienced an overall warmer climate. With a capture-mark-recapture approach, we showed that larger individuals had higher survival rates, demonstrating that weather conditions in early life could have long-lasting fitness effects. The different responses in body size to warmer temperatures in the two regions highlight that fitness-relevant morphological responses to climate change have to be viewed on a regional scale and may affect local populations differently.


Assuntos
Quirópteros , Animais , Feminino , Temperatura , Mudança Climática , Alemanha , Estações do Ano , Tamanho Corporal
2.
R Soc Open Sci ; 9(2): 211881, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35223067

RESUMO

Bats are characterized by low reproductive rates in contrast with most of other small mammals. This makes their populations vulnerable when inclement environmental conditions such as cold and rainy weather impair the reproductive success of females. The fine-scale effect of weather on bats, however, remains largely unknown. Using a sliding window analysis approach on an 18-year individualized dataset on six Natterer's bat (Myotis nattereri) colonies, we investigated the effect of fine-scale weather conditions on age-specific reproductive success. We found that increased precipitation during a short time window in spring strongly reduced the probability of successful reproduction of first-year (FY) females. Our data suggest that this time window is concomitant with implantation or early pregnancy, before substantial investment into embryo development. In addition, larger FY had higher reproductive success, suggesting that reproduction may be condition dependent in young females. Reproductive success of older females was not affected by either weather or individual parameters. Our results show that changes in precipitation pattern may compromise the reproductive success of FY females. Further studies are needed to better understand the impact of weather conditions on reproductive success in long-lived bats under climate change scenarios.

3.
Brain Pathol ; 32(2): e13046, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35213080

RESUMO

Meningiomas are the most frequent primary intracranial tumors. The considerable variety of histological subtypes has been expanded by the definition of molecular alterations, which can improve both diagnostic accuracy and determination of individual patient's outcome. According to the upcoming WHO classification of brain tumors, the in-time analysis of frequent molecular events in meningiomas may become mandatory to define meningioma subtypes. We have compiled a custom-made amplicon-based next generation sequencing (NGS) meningioma panel covering the most frequent known recurrent mutations in 15 different genes. In an unselected consecutive meningioma cohort (109 patients) analyzed over a period of 12 months, we detected mutations in 11 different genes, with most frequent alterations in NF2 (43%), AKT1E17K (15%), and TRAF7 (13%). In 39 tumors (36%), two different mutations were detected, with NF2 and SUFU (n = 5) and KLF4 and TRAF7 (n = 5) being the most frequent combinations. No alterations were found in POLR2A, CDKN2A, CDKN2B, and BAP1, and no homozygous CDKN2A/B deletion was detected. NF2 mutations were found in tumors of all WHO grades, whereas mutations in KLF4, TRAF7, and SMO were restricted to WHO grade I meningiomas. In contrast, SMARCE1 and TERT mutations were associated with WHO grade II meningiomas (according to the WHO classification 2016). The distribution of mutations across histological subtypes or tumor localization was in line with the existing literature, with typical combinations like KLF4K409Q /TRAF7 for secretory meningiomas and preferential skull base localization of meningiomas harboring SMO and AKT1E17K mutations. Thus, we present a custom-made NGS meningioma panel providing a time and cost-efficient reliable detection of relevant somatic molecular alterations in meningiomas suitable for daily routine.


Assuntos
Neoplasias Encefálicas , Neoplasias Meníngeas , Meningioma , Proteínas Cromossômicas não Histona , Proteínas de Ligação a DNA , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Neoplasias Meníngeas/genética , Meningioma/genética , Mutação
4.
Opt Express ; 15(2): 449-58, 2007 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-19532262

RESUMO

We report a 236 nm light source with 20 mW of average power based on critically phase-matched second-harmonic generation in a beta-barium borate crystal at room temperature. The fundamental light source was a passively Q-switched 946 nm Nd:YAG laser tunable from 10 - 38 kHz and with a pulse length of 16 ns. In the generation of 473 nm light, periodically poled KTP and BiBO was compared in terms of conversion efficiency and stability.

5.
Opt Lett ; 34(7): 1024-6, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19340207

RESUMO

Two functions normally attributed to Pockels cells are performed with internal-electrode microstructured fiber components. Single-pulse selection out of a 100 MHz mode-locked pulse train is demonstrated using all-fiber nanosecond polarization rotation. Additionally, off-on-off gating with duration approximately 13 ns is achieved with a polarization rotator made out of a four-hole silicate fiber.

6.
Appl Opt ; 43(24): 4753-67, 2004 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-15352402

RESUMO

An analytical model of cw quasi-three-level lasers that includes the influence of energy-transfer upconversion (ETU) has been developed. The results of the general output modeling were applied to a laser with Gaussian beams, and rigorous numerical calculations have been made to study the influence of ETU on threshold, output power, spatial distribution of population-inversion density, and fractional thermal loading. The model was applied to a laser operating at 946 nm in Nd:YAG, where the dependence of laser-beam size on laser performance was investigated in particular. A simple model for the degradation of laser-beam quality from a transversally varying saturated gain is proposed that is in good agreement with measurements of the laser in a plane-plane cavity.

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