Intermediate Proportion Research Articles

Color polymorphism in an aphid is maintained by attending ants.

The study of polymorphisms is particularly informative for enhancing our understanding of phenotypic and genetic diversity. The persistence of polymorphism in a population is generally explained by balancing selection. Color polymorphisms that are often found in many insects and arthropods are prime examples of the maintenance of polymorphisms via balancing selection. In some aphids, color morphs are maintained through frequency-dependent predation by two predatory insects. However, the presence of color polymorphism in ant-attended aphids cannot be explained by traditional balancing selection because these aphids are free from predation. We examined the selective advantages of the existence of two color (red and green) morphs in the ant-attended aphid, Macrosiphoniella yomogicola, in fields. We measured the degree of ant attendance on aphid colonies with different proportions of color morphs. The results show that the ants strongly favor aphid colonies with intermediate proportions of the two color morphs. The relationship between the degree of ant attendance and the proportion of color morphs in the field is convex when aphid colony size and ant colony size are controlled. This function has a peak of approximately 65% of green morphs in a colony. This system represents the first case of a balancing polymorphism that is not maintained by opposing factors but by a symbiotic relationship.

Human classical monocytes display unbalanced M1/M2 phenotype with increased atherosclerotic risk and presence of disease.

Specific monocyte and macrophage subsets have been implicated in atherosclerosis, with intermediate monocytes proportionally elevated in cardiovascular disease and M1 macrophages abundant in unstable atherosclerotic plaques. While several studies have shown altered proportions of these subsets in atherosclerosis, studies examining functional and phenotypic subset alterations remain scarce. We used whole blood flow cytometry to investigate the expression of M1 (CD86) and M2 (CD163) markers on monocyte subsets of atherosclerotic patients and controls. Atherosclerotic patients had a more inflammatory monocyte profile than controls, indicated by increased intermediate subset proportions, a higher classical monocyte CD86/CD163 ratio, and elevated serum M1-related chemokines. A more inflammatory profile appeared to correlate with atherosclerotic risk, as in controls classical monocyte CD86/CD163 ratio was negatively correlated with HDL and apolipoprotein A1, and positively correlated with interleukin-1β. We conclude that monocyte subsets show functional and phenotypic changes in cardiovascular disease and such changes are likely to contribute to atherosclerotic progression.

The Association between Total Mixed Ration Particle Size and Fecal Scores in Holstein Lactating Dairy Cows from Florida, USA

The objective of this study was to determine the association between the proportion of particles greater than 19 mm in a total mixed ration fed to dairy cattle and their fecal score. Over a 22 day period, random feed samples were collected twice a day from a one-side barn and assessed for particle size using the Pennsylvania State Particle Separator. In addition, at each feeding sampling, the same barn was inspected and fresh feces were scored on a four point scale. Multiple regression models were developed to associate the proportion of particles >19 mm with fecal scores at one, two and three days after that specific particle evaluation. Results of this observational study showed a significant relationship between particle size and fecal scores two days later. The results demonstrated a cubic polynomial effect: Fecal scores improved with increasing of the proportion of particle size >19 mm at a low proportion of large particles, then it was maintained constant at intermediate proportion (10-15%) of large particles and finally increased again with a high proportion (up to 17%) of particle >19 mm.

林地面积比例梯度下景观组成和构型对生物多样性的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 林地面积比例梯度下景观组成和构型对生物多样性的影响 DOI: 10.5846/stxb201410011945 作者: 作者单位: 河南大学,河南大学,河南大学,河南大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金资助项目(41471146,41071118);河南省高校青年骨干教师资助计划项目(2012GGJS-031) Effects of woodland composition and configuration along a woodland area ratio gradient on biodiversity conservation Author: Affiliation: College of Environment and Planning，Henan University，Kaifeng,College of Environment and Planning，Henan University，Kaifeng,College of Environment and Planning，Henan University，Kaifeng,College of Environment and Planning，Henan University，Kaifeng Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以黄河中下游郑州地区为研究区域,根据林地面积比例高低,把确定的260块景观区域划分为林地面积比例高(>50%)、中等(50%-30%)、低(30%-10%)和非常低(<10%)共4个不同类型;采用概率连接度指数(PC)表征林地栖息地可用性程度。利用R软件里的广义线性模型(GLM),分析了10、50、100、250、500、1000、2000 m和3000 m物种不同扩散能力下,反映林地景观组成和构型特征的林地面积比例(PA),以及林地面积比例(PA)与林地斑块数量(NP)、林地平均斑块大小(PS)、林地斑块隔离度(PI)组合作用对栖息地可用性的影响。结果表明:在林地面积比例高的区域,林地面积比例是决定栖息地可用性程度的重要影响因素;在林地面积比例中等的区域,除林地面积比例外,林地斑块隔离度和平均斑块大小是主要影响因素;在林地面积比例低和较低时,依据物种扩散能力的不同,需要考虑平均斑块大小和林地斑块数量的影响。景观中不同林地面积比例情况下,生物保护措施和管理要依据林地面积比例、林地斑块数量、林地平均斑块大小、以及林地斑块隔离度。 Abstract:Biodiversity is one of the key factors affecting ecosystem services, and there are very close connections between agricultural ecosystem and species diversity. The expansion of agricultural land and enhancement of land intensive utilization cause great pressure on the protection of agricultural landscape biodiversity. In highly intensive agriculture landscape, woodlands are important habitats for biodiversity protection. Reduction of the vegetation coverage can lead to changes of habitat patch composition and configuration, which mainly including the decrease of mean patch size and increase of patch isolation degree and number of patches, then impacts species dispersal and settlement. Landscape heterogeneity can affect a variety of ecosystem processes, functions and ecosystem services. The composition and structure of biological habitats in agricultural landscape have an important role in maintaining species diversity. This also makes the transformation of biodiversity protection approaches from species centered to multifunctional landscape planning. Though the composition of landscape habitat patches is crucial for species survival, whether organisms can migrate successfully from one habitat patch to another or not also depends on the landscape connectivity between the two patches. The landscape connectivity level is determined by landscape structure and organisms' behavior characteristics together. To avoid species loss in landscape level, enhancing landscape connectivity becomes particularly important. The aim of this study is to investigate the contribution of the proportion of woodlands area (PA), number of patches (NP), mean patch size (PS), mean patch isolation (PI) for habitat availability (characterizing by probability index of connectivity, PC) along a gradient of woodlands area. Zhengzhou, Henan Province, a typical agricultural region in the middle and lower reaches of the Yellow River, was selected as the case study area. The mixed-effects models (Multi-model Inference, MMI) were applied to model the effects of woodlands landscape characteristics and habitat availability. The explanatory variables are landscape characteristics, namely PA, NP, PS, PI, and eight hypothetical species dispersal abilities (10、50、100、250、500、1000、2000 m and 3000 m). 260 landscapes units are classified into four scenarios according to the proportion of woodlands area, high ( > 50%), intermediate (50%-30%), low (30%-10%) and very low ( < 10%). The analytical results show that, in regions with high proportion of woodlands area ( > 50%), the proportion of woodlands area is the most important factor that affects the degree of habitat availability. In regions with intermediate proportion of woodlands area (50%-30%), besides the proportion of woodlands area, mean patch isolation and mean patch size are the main factors that must be considered. In regions with low and very low proportion of woodlands area ( < 30%), depending on the different species dispersal abilities, it is need to consider the effect of mean patch size and number of patches. For landscape management, we suggest that, conservation efforts should focus on maintaining the current forest, especially in landscapes with high proportion of woodlands area. While in landscapes with intermediate and low proportion of woodlands area, restoration should aim at enhancing habitat availability and reducing isolation. In the regions with very low proportion of woodlands area, managers must put the habitat restoration in the first place to avoid local extinction. 参考文献 相似文献 引证文献

Early-Stage White Matter Lesions Detected by Multispectral MRI Segmentation Predict Progressive Cognitive Decline.

White matter lesions (WML) are the main brain imaging surrogate of cerebral small-vessel disease. A new MRI tissue segmentation method, based on a discriminative clustering approach without explicit model-based added prior, detects partial WML volumes, likely representing very early-stage changes in normal-appearing brain tissue. This study investigated how the different stages of WML, from a “pre-visible” stage to fully developed lesions, predict future cognitive decline. MRI scans of 78 subjects, aged 65–84 years, from the Leukoaraiosis and Disability (LADIS) study were analyzed using a self-supervised multispectral segmentation algorithm to identify tissue types and partial WML volumes. Each lesion voxel was classified as having a small (33%), intermediate (66%), or high (100%) proportion of lesion tissue. The subjects were evaluated with detailed clinical and neuropsychological assessments at baseline and at three annual follow-up visits. We found that voxels with small partial WML predicted lower executive function compound scores at baseline, and steeper decline of executive scores in follow-up, independently of the demographics and the conventionally estimated hyperintensity volume on fluid-attenuated inversion recovery images. The intermediate and fully developed lesions were related to impairments in multiple cognitive domains including executive functions, processing speed, memory, and global cognitive function. In conclusion, early-stage partial WML, still too faint to be clearly detectable on conventional MRI, already predict executive dysfunction and progressive cognitive decline regardless of the conventionally evaluated WML load. These findings advance early recognition of small vessel disease and incipient vascular cognitive impairment.

Timing matters: corticosterone injections 4 h before ovulation bias sex ratios towards females in chickens.

Birds have the ability to influence offspring sex prior to egg laying and may use hormones to mediate these skews. Corticosterone is of particular interest as a mediator of offspring sex because, as the primary stress hormone in birds, it regulates responses to environmental and social stimuli that trigger sex ratio biases. In previous studies in birds, chronic elevations of corticosterone stimulated female-biased sex ratios while acute pharmacological elevations that were provided 5 h prior to the expected time of ovulation stimulated male-biased sex ratios. Here, we aimed to determine the magnitude of corticosterone necessary to influence offspring sex and to further pinpoint the timing of the hormonal influence. Because high-dose injections of corticosterone stimulated male-biased sex ratios in hens, we hypothesized that females receiving acute pharmacological elevations of corticosterone would produce more male offspring while females with acute physiological elevations would produce an intermediate proportion of males compared to controls. We tested our hypotheses in laying hens by elevating corticosterone in the physiological or pharmacological range through injections of corticosterone administered 4 or 5 h prior to the expected time of ovulation. Contrary to our hypothesis, a physiological dose of corticosterone provided 5 h prior to the expected time of ovulation did not bias offspring sex ratios when compared to controls. Further, when corticosterone injections were given at 4 h prior to the expected time of ovulation, sex ratios were instead biased towards females. These results suggest that the timing and magnitude of the corticosterone elevation are both critical not only to whether a sex ratio bias occurs, but also the direction of the bias.

Comparison of fatty acids in beef tissues from conventional, organic and natural feeding systems in western Canada

Turner, T. D., Jensen, J., Pilfold, J. L., Prema, D., Donkor, K. K., Cinel, B., Thompson, D. J., Dugan, M. E. R. and Church, J. S. 2015. Comparison of fatty acids in beef tissues from conventional, organic and natural feeding systems in western Canada. Can. J. Anim. Sci. 95: 49–58. The effect of production system on intramuscular and associated trim fatty acid (FA) profiles of retail ribeye steaks from conventional and niche market organic and natural (grain- or grass-fed) beef were compared. Meat from organic grain- and grass-fed systems was leaner, containing greater proportions of polyunsaturated FA, i.e., 18:3n-3, 20:5n-3, 22:5n-3, 22:6n-3. Correspondingly, the n-6/n-3 ratios of organic grain- and grass-fed systems were 3:1, while conventional and natural grain systems had ratios of 8:1. High forage-to-grain ratio production systems increased proportions of desirable biohydrogenation intermediates (BI), including t11-18:1 and c9,t11-18:2, whereas conventional and natural grain systems elevated t10-18:1. Trim fat was similarly affected by production system, and was a relatively richer source of BI. Overall, proportions of desirable FAs, including n-3 and BI, were greater for organic grain- and grass-fed systems, emphasizing the importance of a high forage-to-grain ratio to enhance the healthfulness of beef, whereas conventional and natural grain-fed systems were largely equivalent.

Dynamic hypoxic zones in Lake Erie compress fish habitat, altering vulnerability to fishing gears

Seasonal degradation of aquatic habitats from hypoxia occurs in numerous freshwater and coastal marine systems and can result in direct mortality or displacement of fish. Yet, fishery landings from these systems are frequently unresponsive to changes in the severity and extent of hypoxia, and population-scale effects have been difficult to measure except in extreme hypoxic conditions with hypoxia-sensitive species. We investigated fine-scale temporal and spatial variability in dissolved oxygen in Lake Erie as it related to fish distribution and catch efficiencies of both active (bottom trawls) and passive (trap nets) fishing gears. Temperature and dissolved oxygen loggers placed near the edge of the hypolimnion exhibited much higher than expected variability. Hypoxic episodes of variable durations were frequently punctuated by periods of normoxia, consistent with high-frequency internal waves. High-resolution interpolations of water quality and hydroacoustic surveys suggest that fish habitat is compressed during hypoxic episodes, resulting in higher fish densities near the edges of hypoxia. At fixed locations with passive commercial fishing gear, catches with the highest values occurred when bottom waters were hypoxic for intermediate proportions of time. Proximity to hypoxia explained significant variation in bottom trawl catches, with higher catch rates near the edge of hypoxia. These results emphasize how hypoxia may elevate catch rates in various types of fishing gears, leading to a lack of association between indices of hypoxia and fishery landings. Increased catch rates of fish at the edges of hypoxia have important implications for stock assessment models that assume catchability is spatially homogeneous.

Enhanced Electrooxidation of Ethanol Using Pd/C + TiO2 Electrocatalysts in Alkaline Media

This work describes the use of Pd nanoparticles synthetized by the borohydride process and supported on physical mixtures of C + TiO2 toward the ethanol electrooxidation reaction in alkaline media. In this study, the C/TiO2 ratios were studied by ranging the mass proportions of C/TiO2—100:0, 80:20, 60:40, 40:60, 20:80, and 0:100. X-ray diffraction patterns showed the presence of Pd face-centered cubic (fcc) structure, and carbon and TiO2 in rutile and anatase phases. Transmission electron micrographs showed metal nanoparticles with average particle size between 5.5 and 7.2 nm for all electrocatalysts. Cyclic voltammograms of Pd/C + TiO2 electrocatalysts showed a decrease of Pd surface area with the TiO2 increasing, while the linear sweep and chronoamperometric results showed the Pd/C + TiO2 (40:60) as the most promising electrocatalyst toward ethanol electrooxidation. The best results obtained with this catalyst were attributed to the presence of carbon and TiO2 in intermediate proportions since TiO2 supplies OH species and also changes the Pd d-band by a strong metal support interaction, increasing the alcohol oxidation without a significant decrease of conductivity and surface area.

Decreasing abundance, increasing diversity and changing structure of the wild bee community (Hymenoptera: Anthophila) along an urbanization gradient.

BackgroundWild bees are important pollinators that have declined in diversity and abundance during the last decades. Habitat destruction and fragmentation associated with urbanization are reported as part of the main causes of this decline. Urbanization involves dramatic changes of the landscape, increasing the proportion of impervious surface while decreasing that of green areas. Few studies have investigated the effects of urbanization on bee communities. We assessed changes in the abundance, species richness, and composition of wild bee community along an urbanization gradient.Methodology/Principal FindingsOver two years and on a monthly basis, bees were sampled with colored pan traps and insect nets at 24 sites located along an urbanization gradient. Landscape structure within three different radii was measured at each study site. We captured 291 wild bee species. The abundance of wild bees was negatively correlated with the proportion of impervious surface, while species richness reached a maximum at an intermediate (50%) proportion of impervious surface. The structure of the community changed along the urbanization gradient with more parasitic species in sites with an intermediate proportion of impervious surface. There were also greater numbers of cavity-nesting species and long-tongued species in sites with intermediate or higher proportion of impervious surface. However, urbanization had no effect on the occurrence of species depending on their social behavior or body size.Conclusions/SignificanceWe found nearly a third of the wild bee fauna known from France in our study sites. Indeed, urban areas supported a diverse bee community, but sites with an intermediate level of urbanization were the most speciose ones, including greater proportion of parasitic species. The presence of a diverse array of bee species even in the most urbanized area makes these pollinators worthy of being a flagship group to raise the awareness of urban citizens about biodiversity.

Effects of pistachio by-products on digestibility, milk production, milk fatty acid profile and blood metabolites in Saanen dairy goats.

The objective of this study was to investigate the effects of pistachio by-products (PBP) on nutrient digestibility, blood metabolites and milk fatty acid (FA) profile in Saanen dairy goats. Nine multiparous lactating Saanen goats (on day 90 post-partum, 45±2/kg BW) were randomly assigned to a 3×3 Latin square design with three treatment diets: 1) control diet (alfalfa hay based), 2) 32% PBP and 3) 32% PBP+polyethylene glycol (PEG-4000; 1g/kg dry matter). Each period lasted 21days, including 14day for treatment adaptation and 7day for data collection. Pistachio by-products significantly decreased (p<0.01) crude protein (CP) digestibility compared with the control diet (64.4% vs. 58.7%), but PEG addition did not differ for CP digestibility of goats fed 32% PBP+PEG and those fed the two other diets. The digestibility of NDF tended (p=0.06) to decrease for goats fed PBP compared with those fed the control diet. Yields of milk and 4% fat-corrected milk were not affected by dietary treatments. Compared with the control diet, PBP supplementation appreciably changed the proportions of almost all the milk FA measured; the main effects were decreases (p<0.01) in FA from 8:0 to 16:0 and increases (p<0.01) proportions of cis-9, trans-11 18:2 and trans-11 18:1, monounsaturated FA, polyunsaturated FA and long-chain FA. The saturated FA, short-chain FA and medium-chain FA proportions were lower (p<0.01) in goats fed the two PBP supplemented diet than in those fed the control diet and PEG addition led to intermediate proportions of saturated FA, unsaturated and monounsaturated FA. Inclusion of PBP in the diet decreased (p<0.01) plasma concentrations of glucose and urea nitrogen compared with the control diet. It was concluded that PBP can be used as forage in the diet of dairy goats without interfering with milk yield. Inclusion of 32% PBP in the diet of dairy goats had beneficial effects on milk FA profile but PEG addition to PBP did not contribute to enhance further milk FA profile.

Effect of the TiO2 content as support with carbon toward methanol electro-oxidation in alkaline media using platinum nanoparticles as electrocatalysts

Platinum nanoparticles supported on physical mixtures of Vulcan carbon and TiO2 (Pt/(C + TiO2)) were prepared by the borohydride method and tested for methanol electro-oxidation in alkaline media. X-ray diffraction (XRD) analyses showed peaks characteristic of Pt face-centered cubic (fcc) structure and peaks associated with TiO2 and carbon. Transmission electron microscopy (TEM) images showed the Pt nanoparticles distributed preferentially over the TiO2 support with average particle sizes between 5 and 6 nm. Cyclic voltammograms showed a decrease of Pt surface area with increasing TiO2 load while linear sweep in the presence of methanol showed Pt/(C + TiO2) (60:40) with the highest current density in accordance with chronoamperometry. The results were attributed to Pt-based nanoparticles on TiO2 which show enhanced catalytic activities for methanol oxidation due to a metal-support interaction. Furthermore, TiO2 is a semiconductor with low conductivity when compared to carbon. Thus, it is expected that an intermediate proportion of carbon and TiO2 as substrate could improve the activity of Pt nanoparticles without substantial loss of conductivity, resulting in a synergic effect.

The morphology of Oreopithecus bambolii pollical distal phalanx

Oreopithecus bambolii is a Late Miocene ape from Italy, first described in the late 19th century. Its interpretation is still highly controversial, especially in reference to its hand proportions and thumb morphology. In this study, the authors provide detailed descriptions of the available Oreopithecus pollical distal phalanx (PDP) specimens, as well as bivariate and multivariate morphometric analyses in comparison with humans, extant apes, selected anthropoid monkeys, and available Miocene PDP specimens. The multivariate results reveal two opposite poles on the hominoid PDP shape spectrum: on one side, a mediolaterally broad and dorsopalmarly short human PDP, and on the other side, the narrow and "conical" PDP of chimpanzees and orangutans. The authors contend that Oreopithecus exhibits intermediate PDP proportions that are largely primitive for hominoids because it shares morphological similarities with Proconsul. Furthermore, Oreopithecus displays a mediolaterally wide tuft for a hominoid, as well as a palmarly elevated attachment for a long tendon of a flexor muscle that is associated at its proximal edge with a proximal fossa and at its distal edge with an ungual fossa. These nonmetrical traits have been associated in humans with their capability to oppose and contact the proximal pads of the thumb and fingers, that is, pad-to-pad precision grasping. These traits reinforce previous studies that indicate a human-like thumb-to-hand length ratio compatible with pad-to-pad precision grasping in Oreopithecus. Although specific hand use is still unresolved in Oreopithecus, the results suggest enhanced manipulative skills (unrelated to stone tool-making) in this taxon relative to other (extant or fossil) hominoids.

Phenotypic characterisation of immune cell infiltrates in testicular germ cell neoplasia

Immune cells often infiltrate testicular germ cell neoplasms, including pre-invasive carcinoma in situ (CIS), but the significance of this phenomenon remains unknown. The composition and distribution of infiltrating immune cells were examined by immunohistochemistry in testis samples with CIS and overt seminoma, in comparison to biopsies from infertile men without neoplasia. The composition of immune cells was similar across all the groups studied. Macrophages, CD8+ and CD45R0+ T lymphocytes constituted the majority of infiltrates, B lymphocytes were present in an intermediate proportion and very few CD4+ and FoxP3+ T cells were detected. HLA-I antigen was more abundant in Sertoli cells in tubules containing CIS than in those with normal spermatogenesis. This study showed a phenotypically comparable composition of infiltrating immune cells independently of the presence of neoplasia, suggesting the absence of active immune surveillance in testicular germ cell cancer.

Two interbreeding populations ofSaccharomyces cerevisiaestrains coexist in cachaça fermentations from Brazil

In this study, the phylogenetic relationships between cachaça strains of Saccharomyces cerevisiae isolated from different geographical areas in Brazil were obtained on the basis of sequences of one mitochondrial (COX2) and three nuclear (EGT2, CAT8, and BRE5) genes. This analysis allowed us to demonstrate that different types of strains coexist in cachaça fermentations: wine strains, exhibiting alleles related or identical to those present in European wine strains; native strains, containing alleles similar to those found in strains isolated from traditional fermentations from Latin America, North America, Malaysian, Japan, or West Africa; and their intraspecific hybrids or 'mestizo' strains, heterozygous for both types of alleles. Wine strains and hybrids with high proportions of wine-type alleles predominate in southern and southeastern Brazil, where cachaça production coexists with winemaking. The high frequency of 'wine-type' alleles in these regions is probably due to the arrival of wine immigrant strains introduced from Europe in the nearby wineries due to the winemaking practices. However, in north and northeastern states, regions less suited or not suited for vine growing and winemaking, wine-type alleles are much less frequent because 'mestizo' strains with intermediate or higher proportions of 'native-type' alleles are predominant.

Synthesis and characterization of four new halloysite–TiO2 nanocomposites.

The synthesis as well as the characterization of small-sized TiO2 particles supported on Halloysite are presented. Hallloysite from Utah, USA as well as from Limnos, island Greece, were used to synthesize two nanocomposites for each halloysite with TiO2 to halloysite weight ratios of 80: 20 and 60:40 and compare with published data of well formed nanocomposites of intermediate proportion (70-30) that were previously studied. All nanocomposites were prepared by deposition of anatase (TiO2) on the halloysite tubes using a sol–gel method under hydrothermal treatment at 180 °C. Phase composition, particle morphology and physical properties of these samples were characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Attenuated Total Reflection using Fourier Transform Infrared spectroscopy (ATR-FTIR) and N2 surface area analysis by BET. Preparation of all halloysite–TiO2 nanocomposites led to the anticipated good dispersion of anatase particles on halloysite surfaces. ATR-FTIR results revealed the formation of hydrogen bonding between anatase and the outer surfaces of halloysite tubes. All halloysite-TiO2 nanocomposites largely showed interparticle mesopores of about 5.7nm and high SSAs.

Pre and perinatal aspects of congenital cystic adenomatoid malformation of the lung

Objective: To identify the incidence of congenital cystic adenomatoid malformation of the lung (CCAM) at birth; to evaluate prenatal and perinatal history, association with clinical and sociodemographic variables and concordance between CT scan results and anatomopathology studies.Method: Descriptive study based on the registry of malformed newborns, deliveries and patients records between August 1990 and November 2010. Ultrasonic, clinical, imaging and anatomopathologic information were studied. Association studies were made using chi-square test. Kappa was used to correlate CT scan to anatomopathology results.Results: The incidence was 1:1980 (25/49 503). The mean gestational age for detection by ultrasonography was 24 ± 3.7 weeks. There were progression of the lesions in 11 cases (44%), stability in 6 (24%) and regression in 8 (32%). Three cases of CCAM followed due to polyhydramnios/hydrops died. There were neither familial cases nor association with sex, weight, age or maternal parity (p > 0.15). Radiographic abnormalities were found in 22/23 studied patients. The correspondence between CT scan and anatomopathologic was 0.77 (Kappa).Conclusions: The incidence was higher than the one described in the literature, probably, because it is a reference center in fetal medicine. The prenatal lesion involution rate was 32%, an intermediate proportion. There was good concordance between CT scan and anatomopathologic results. The polyhydramnios/hydrops were predictive of worst prognosis.

Species Composition of Termites (Isoptera) in Different Cerrado Vegetation Physiognomies

Little is known about the termite fauna of the different vegetation physiognomies in the Cerrado biome. It is suggested that the species compositions in grassland and savanna areas are closely related to each other, and quite distinct from those of forests. This study compared the species composition from five different physiognomies of Cerrado, and tested the hypothesis that the termite faunas of savannas and grasslands form a distinct group from that of forests. The study was conducted in the Parque Estadual da Serra de Jaraguá, state of Goiás, Brazil. Termites were sampled from two physiognomies of savanna, one natural grassland, one pasture, and one gallery forest. A transect with 10 parcels of 5x2 m was established in each physiognomy. The relative abundance was inferred by the number of encounters, termites were classified in feeding guilds, and the dissimilarity in the species composition between the physiognomies was calculated. A total of 219 encounters, of 42 species of two families were recorded. The most abundant feeding guilds were the humivores (98) and xylophages (55). The physiognomies with the largest number of species were rupestrian cerrado (23 species) and cerrado sensu stricto (21). The physiognomies had a similar species composition (less than 55% dissimilarity), mainly the natural open areas. The hypothesis of a distinct fauna of termites in forest vegetation was refuted. The termite fauna of gallery forest is very different from that of pasture, but most species also occur in natural open areas. The impact of pasture on the diversity and composition of termites seems to be significant, but the impact is even greater on the proportion of the feeding guilds, reducing the proportion of xylophages and intermediates.

Closing in on maximum yield of chlorophyll fluorescence using a single multiphase flash of sub‐saturating intensity

Estimation of the maximum chlorophyll fluorescence yield under illumination, or Fm', by traditional single saturation pulse (SP) methodology is prone to underestimation error because of rapid turnover within photosystem (PS) II. However, measurements of fluorescence yield during several single pulses of variable intensity describes the irradiance dependence of apparent Fm', from which estimates of Fm' at infinite irradiance can be derived. While such estimates have been shown to result in valid approximations of Fm', the need to apply several single pulses limits its applicability. We introduce a novel approach that determines the relationship between apparent Fm' and variable irradiance within a single ∼1 s multiphase flash (MPF). Through experiments and simulations, we demonstrate that the rate of variation in irradiance during an MPF is critical for achieving quasi-steady-state changes in the proportions of PSII acceptor side redox intermediates and the corresponding fluorescence yields, which are prerequisites for accurately estimating Fm' at infinite irradiance. The MPF methodology is discussed in the context of improving the accuracy of various parameters derived from chlorophyll fluorescence measurements, such as photochemical and non-photochemical quenchings and efficiencies. The importance of using MPF methodology for interpreting chlorophyll fluorescence, in particular for integrating fluorescence and gas exchange measurements, is emphasized.

Barium-Triel-Mercuride BaMxHg4-x und Ba3MxHg11-x (M=Ga, In, Cd) / Barium Triel Mercurides BaMxHg4-x and Ba3MxHg11-x (M =Ga, In, Cd)

The systematic experimental and bond-theoretical study of the phase width of the BaAl4 structure type in the ternary system BaIn4- BaHg4 shows that this structure type is stable up to BaIn1:7Hg2:3 (tetragonal, tI10, space group I4=mmm, a=474.2(3), c=1228.7(9) pm, R1=0.0529). The planar 44 layers (M(2) site) are preferentially formed by In, whereas Hg occupies the tips (M(1) site) of the [M(1)M(2)4] square pyramids. The layers of the pyramids are connected via short M(1)-M(1) dumbbells (bonds a). The analysis of the calculated band structures of BaIn2Hg2 in comparison to BaIn4 and RbIn4 shows that contributions of Ba-d states (which are missing for RbIn4) and Hg-d states (which are missing in the pure indides) are significant. The respective compound with the smaller triel gallium (Hg-richest phase: BaGa1:9Hg2:1, tetragonal, oI40, space group I41=amd, a=671.3(2), c=2220.4(8) pm, Z =8, R1=0.0641) forms a new superstructure of the BaAl4 structure with a partial ordering of three statistically occupied mixed Ga=Hg positions. The 44 nets are formed by an intermediate proportion of Ga=Hg. The tips of the pyramids are alternately formed by a Ga- and an Hg-rich position leading to smaller and larger bond lengths a’ and a”, respectively, between the tip atoms and, consequentely, a puckering of the 44 net. The two Hg-rich 3 : 11 compounds Ba3InHg10 and Ba3CdHg10 (orthorhombic, oI28, space group Immm, a=513.96(8)=511.50(2), b=993.8(2)=991.54(3), c=1500.7(3)=1499.26(5) pm, Z =2, R1=0.0619=0.0482) crystallize in the La3Al11 structure type, which is also observed for K3Hg11 and is closely related to the BaAl4 type: The square pyramidal nets are corrugated leading to a triplication of the BaAl4 unit cell along one of the tetragonal axes. In each third subcell the tips of adjacent pyramids are directly fused, this position being occupied exclusively by In and Cd. With the smaller triel gallium, the 3 : 11 compound Ba3Ga0:2Hg10:8 crystallizes in the Ba3ZnHg10 structure type (orthorhombic, oP28, space group Pmmn, a=709.36(4), b=1707.96(9), c=630.78(4) pm, Z =2, R1=0.0342). The structure contains folded layers of flat rectangular Ga=Hg pyramids, leaving large channels at the folds, in which Ba(1) and Hg(2) atoms alternate. The formation and stability ranges of 1 : 4, 3 : 11 and related 5 : 19 trieles/mercurides are discussed taking geometric, electronic and M13=Hg ,coloring‘ aspects into account.