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51.
Data obtained during an ongoing dental investigation of African populations address two long-standing, hotly debated questions. First, was there genetic continuity between Late Pleistocene Iberomaurusians and later northwest Africans (e.g., Capsians, Berbers, Guanche)? Second, were skeletally-robust Iberomaurusians and northeast African Nubians variants of the same population? Iberomaurusians from Taforalt in Morocco and Afalou-Bou-Rhummel in Algeria, Nubians from Jebel Sahaba in Sudan, post-Pleistocene Capsians from Algeria and Tunisia, and a series of other samples were statistically compared using 29 discrete dental traits to help estimate diachronic local and regional affinities. Results revealed: (1) a relationship between the Iberomaurusians, particularly those from Taforalt, and later Maghreb and other North African samples, and (2) a divergence among contemporaneous Iberomaurusians and Nubian samples. Thus, some measure of long-term population continuity in the Maghreb and surrounding region is supported, whereas greater North African population heterogenity during the Late Pleistocene is implied.  相似文献   
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The shoot apical meristem of Arabidopsis thaliana consists of three cell layers that proliferate to give rise to the aerial organs of the plant. By labeling cells in each layer using an Ac-based transposable element system, we mapped their contributions to the floral organs, as well as determined the degree of plasticity in this developmental process. We found that each cell layer proliferates to give rise to predictable derivatives: the L1 contributes to the epidermis, the stigma, part of the transmitting tract and the integument of the ovules, while the L2 and L3 contribute, to different degrees, to the mesophyll and other internal tissues. In order to test the roles of the floral homeotic genes in regulating these patterns of cell proliferation, we carried out similar clonal analyses in apetala3-3 and agamous-1 mutant plants. Our results suggest that cell division patterns are regulated differently at different stages of floral development. In early floral stages, the pattern of cell divisions is dependent on position in the floral meristem, and not on future organ identity. Later, during organogenesis, the layer contributions to the organs are controlled by the homeotic genes. We also show that AGAMOUS is required to maintain the layered structure of the meristem prior to organ initiation, as well as having a non-autonomous role in the regulation of the layer contributions to the petals.  相似文献   
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BackgroundThe use of near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) for sentinel lymph node (SN) mapping has been investigated in lung cancer; however, this has not been fully adapted for minimally invasive surgery (MIS). The aim of our study was to develop a minimally invasive SN mapping integrating pre-operative electro-magnetic navigational bronchoscopy (ENB)-guided transbronchial ICG injection and intraoperative NIR thoracoscopic imaging.MethodsA NIR thoracoscope was used to visualize ICG fluorescence. ICG solutions in a 96-well plate and ex vivo porcine lungs were examined to optimize ICG concentrations and injection volumes. Transbronchial ICG injection (n=4) was assessed in comparison to a traditional transpleural approach (n=3), where after thoracotomy an ICG solution (100μL at 100μg/mL) was injected into the porcine right upper lobe for SN identification. For further translation into clinical use, transbronchial ICG injection prior to thoracotomy followed by NIR thoracoscopic imaging was validated (n=3). ENB was used for accurate targeting in two pigs with a pseudo-tumor.ResultsThe ICG fluorescence at 10 μg/mL was the brightest among various concentrations, unchanged by the distance between the thoracoscope and ICG solutions. Injected ICG of no more than 500μL showed a localized fluorescence area. All 7 pigs showed a bright paratracheal lymph node within 15 minutes post-injection, with persistent fluorescence for 60 minutes. The antecedent transbronchial ICG injection succeeded in SN identification in all 3 cases at the first thoracoscopic inspection within 20 minutes post-injection. The ENB system allowed accurate ICG injection surrounding the pseudo-tumors.ConclusionsENB-guided ICG injection followed by NIR thoracoscopy was technically feasible for SN mapping in the porcine lung. This promising platform may be translated into human clinical trials and is suited for MIS.  相似文献   
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Plant and Soil - Salinization of soil with sodium chloride ions inhibits plant functions, causing reduction of yield of crops. Salt tolerant microorganisms have been studied to enhance crop growth...  相似文献   
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The disposal of human excreta in latrines is an important step in reducing the transmission of diarrhoeal diseases. However, in latrines, flies can access the latrine contents and serve as a mechanical transmitter of diarrhoeal pathogens. Furthermore, the latrine contents can be used as a breeding site for flies, which may further contribute to disease transmission. Latrines do not all produce flies, and there are some which produce only a few, while others can produce thousands. In order to understand the role of the latrine in determining this productivity, a pilot study was conducted, in which fifty latrines were observed in and around Ifakara, Tanzania. The characteristics of the latrine superstructure, use of the latrine, and chemical characteristics of pit latrine contents were compared to the numbers of flies collected in an exit trap placed over the drop hole in the latrine. Absence of a roof was found to have a significant positive association (t=3.17, p=0.003) with the total number of flies collected, and temporary superstructures, particularly as opposed to brick superstructures (z=4.26, p<0.001), and increased total solids in pit latrines (z=2.57, p=0.01) were significantly associated with increased numbers of blowflies leaving the latrine. The number of larvae per gram was significantly associated with the village from which samples were taken, with the largest difference between two villages outside Ifakara (z=2.12, p=0.03). The effect of latrine superstructure (roof, walls) on fly production may indicate that improvements in latrine construction could result in decreases in fly populations in areas where they transmit diarrhoeal pathogens.  相似文献   
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Moderate chronic kidney disease (CKD) (defined by an estimated glomerular filtration rate of 30–60 ml/min) is associated with mild hypertriglyceridemia related to delayed catabolism of triglyceride-rich lipoprotein particles. Altered apolipoprotein C-III (apoC-III) metabolism may contribute to dyslipidemia in CKD. To further characterize the dyslipidemia of CKD, we investigated the kinetics of plasma apoC-III in 7 nonobese, nondiabetic, non-nephrotic CKD subjects and 7 age- and sex-matched healthy controls, using deuterated leucine ([5, 5, 5, 2H3]leucine), gas chromatography-mass spectrometry, and multicompartmental modeling. Compared with controls, CKD subjects had higher concentrations of plasma and VLDL triglycerides and plasma and VLDL apoC-III (P < 0.05). The increased plasma apoC-III concentration was associated with a decreased apoC-III fractional catabolic rate (FCR) (1.21 ± 0.15 vs. 0.74 ± 0.12 pools/day, P = 0.03). There were no differences between apoC-III production rates of controls and those of CKD subjects. In CKD subjects, plasma apoC-III concentration was significantly and negatively correlated with apoC-III FCR (r = −0.749, P = 0.05) but not with apoC-III production rate. Plasma apoC-III concentration was positively correlated with plasma and VLDL triglycerides and VLDL apoB concentrations and negatively correlated with VLDL apoB FCR (P < 0.05 for all). ApoC-III FCR was negatively correlated with plasma and VLDL triglycerides and VLDL apoB concentration and positively correlated with VLDL apoB FCR (P < 0.05 for all). Altered plasma apoC-III metabolism is a feature of dyslipidemia in moderate CKD. Modification of apoC-III catabolism may be an important therapeutic target for reducing cardiovascular disease risk in moderate CKD.  相似文献   
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