Melittophily and Ornithophily of Long-tubed Flowers in Zingiberaceae and Gesneriaceae in West Sumatra

Pollination of seven zingiberaceous and two gesneriaceous species was studied in natural forests at various altitudes in West Sumatra, Indonesia. Terrestrial, red, long-tubed flowers of Achasma macrocheilos were visited by a large, remarkably long-tongued anthophorine bee, Amegilla elephas. The swiftly-flying bees showed traplining foraging behavior just like euglossine bees in the Neotropics. This bee species was oligolectic to the plant species and almost the only pollinator of it. Yellow (rarely white), long-tubed flowers of Zingiber puberulum, Grobba aurantiaca, Amomum aculeatum and Cyrtandra pendula were pollinated by median-sized, shade-loving, traplining, long-tongued anthophorine bees in the genera Amegilla and Elaphropoda. White, short-tubed flowers of Amomum uliginosum and Cyrtandra aff. grandiflora were pollinated by traplining halictid bees in the genus Nomia. Long-tubed flowers borne on red stout spikes of Hornstedtia aff. conica and Phaeomeriafulgens were pollinated by a long-billed sunbird, Arachnothera longirostra. These ornithophilous flowers produced significantly more nectar of lower sugar concentration than the melittophilous flowers. According to the proboscis lengths, long-tongued bees were classified into three groups, which corresponded to the three pollination guilds of the melittophilous flowers. Among species in a bee guild, convergence of proboscis lengths was detected, and the floral hosts of the bee species were sometimes overlapping. Twenty-five percent of melittophilous species were visited by more than one bee species, but nonetheless most individual plants were visited by only a single bee species. At higher altitudes more than 1400 m, anthophorine bees were displaced by bumblebees and the guild structure of longtongued bees was simpler than at lower altitudes.ArticleTropics. 2(3): 129-142(1993)journal articl

Functional near-infrared spectroscopy studies in children

Psychosomatic and developmental behavioral medicine in pediatrics has been the subject of significant recent attention, with infants, school-age children, and adolescents frequently presenting with psychosomatic, behavioral, and psychiatric symptoms. These may be a consequence of insecurity of attachment, reduced self-confidence, and peer -relationship conflicts during their developmental stages. Developmental cognitive neuroscience has revealed significant associations between specific brain lesions and particular cognitive dysfunctions. Thus, identifying the biological deficits underlying such cognitive dysfunction may provide new insights into therapeutic prospects for the management of those symptoms in children. Recent advances in noninvasive neuroimaging techniques, and especially functional near-infrared spectroscopy (NIRS), have contributed significant findings to the field of developmental cognitive neuroscience in pediatrics. We present here a comprehensive review of functional NIRS studies of children who have developed normally and of children with psychosomatic and behavioral disorders

Historical Evolution Toward Achieving Ultrahigh Vacuum in JEOL Electron Microscopes

This book describes the developmental history of the vacuum system of the transmission electron microscope (TEM) at the Japan Electron Optics Laboratory (JEOL) from its inception to its use in today’s high-technology microscopes. The author and his colleagues were engaged in developing vacuum technology for electron microscopes (JEM series) at JEOL for many years. This volume presents a summary and explanation of their work and the technology that makes possible a clean ultrahigh vacuum. The typical users of the TEM are top-level researchers working at the frontiers of new materials or with new biological specimens. They often use the TEM under extremely severe conditions, with problems sometimes occurring in the vacuum system of the microscopes. JEOL engineers then must work as quickly as possible to improve the vacuum evacuation system so as to prevent the recurrence of such problems. Among the wealth of explanatory material in this book are examples of users’ reports of problems in the vacuum system of the JEM, such as the occurrence of a micro-discharge and the back-streaming of the diffusion pump (DP) oil vapor. This work is a valuable resource for researchers who use the transmission electron microscope and for engineers and scientists interested in its technology

Comparison of the Electronic Structures of Two Non-cuprate Layered Transition Metal Oxide Superconductors

Comparison is made of the electronic structure of the little-studied layered transition metal oxide LiNbO$_2$ with that of Na$_x$CoO$_2$, which has attracted tremendous interest since superconductivity was discovered in its hydrate. Although the active transition metal $d$ states are quite different due to different crystal fields and band filling, both systems show a strong change of electronic structure with changes in the distance between the transition metal ion layer and the oxygen layers. The niobate is unusual in having a large second-neighbor hopping amplitude, and a nearest neighbor hopping amplitude that is sensitive to the Nb-O separation. Li$_x$NbO$_2$ also presents the attractive simplicity of a single band triangular lattice system with variable carrier concentration that is superconducting.Comment: 5 pages, 3 embedded figures (Proceedings in third Hiroshima international workshop

Early diagenesis of plant-derived dissolved organic matter along a wetland, mangrove, estuary ecotone

We studied the role of photochemical and microbial processes in contributing to the transformation of dissolved organic matter (DOM) derived from various plants that dominate the Florida Everglades. Plant-derived DOM leachate samples were exposed to photochemical and microbial degradation and the optical, chemical, and molecular weight characteristics measured over time. Optical parameters such as the synchronous fluorescence intensity between 270 and 290 nm (Fnpeak I), a strong indicator of protein and/or polyphenol content, decreased exponentially in all plant leachate samples, with microbial decay constants ranging from 21.0 d21 for seagrass to 20.11 d21 for mangrove (half-life [t1/2] 5 0.7–6.3 d). Similar decreases in polyphenol content and dissolved organic carbon (DOC) concentration also occurred but were generally an order of magnitude lower or did not change significantly over time. The initial molecular weight composition was reflected in the rate of Fnpeak I decay and suggests that plantderived DOM with a large proportion of high molecular weight structures, such as seagrass derived DOM, contain high concentrations of easily microbially degradable proteinaceous components. For samples exposed to extended simulated solar radiation, polyphenol and Fnpeak I photochemical decay constants were on average 20.7 d21 (t1/2 1.0 d). Our data suggest that polyphenol structures of plant-derived DOM are particularly sensitive to photolysis, whereas high molecular weight protein-like structures are degraded primarily through physical–chemical and microbial processes. Furthermore, microbial and physical processes initiated the formation of recalcitrant, highly colored high molecular weight polymeric structures in mangrove-derived DOM. Thus, partial, biogeochemical transformation of plant-derived DOM from coastal areas is rapid and is likely to influence carbon and nutrient cycling, especially in areas dominated by seagrass and mangrove forests

Seed sourcing for woodland creation in an era of uncertainty: An analysis of the options for Great Britain

In recent years, British seed sourcing practice has tended to focus on the principle that “local-is-best” for native woodland creation. However, in the face of continuing and accelerating environmental change, the suitability of this approach has been called into question. In this article, we investigate the relevance and suitability of a series of seed sourcing strategies: maintaining the status quo by continuing to source local origin seed, sourcing seed from currently warmer locations, and the addition or replacement of species. Our main findings are that there are opportunities to increase the sophistication of existing guidance and that improvements would be timely. In any case, an important consideration is the capacity for newly established populations of trees to survive immediately and amidst increasingly variable environmental conditions. The current paucity of knowledge of forest genetic resources in British populations of native tree species suggests that deviations from sourcing currently adapted planting stock are not uniformly applicable throughout the country and that any change to policy ought to be applied judiciously and only under a restricted set of circumstances

Investigation of frontal lobe activation with fNIRS and systemic changes during video gaming.

Frontal lobe activation caused by tasks such as videogames can be investigated using multichannel near-infrared spectroscopy (fNIRS), sometimes called optical topography. The aims of this study are to investigate the effects of video gaming (fighting and puzzle games) in the brain and the systemic physiology and to determine whether systemic responses during the gaming task are associated with the measurement of localised cerebral haemodynamic changes as measured by fNIRS. We used a continuous-wave 8-channel fNIRS system to measure the changes in concentration of oxy-haemoglobin (HbO2) and deoxy-haemoglobin (HHb) and changes in total haemoglobin (ΔtHb = ΔHbO2 + ΔHHb) over the frontal lobe in 30 healthy volunteers. The Portapres system was used to measure mean blood pressure (MBP) and heart rate (HR), and a laser Doppler was employed to measure the changes in scalp blood flow (or flux). Even though we observed significant changes in systemic variables during gaming, in particular in scalp flow, we also managed to see localised activation patterns over the frontal polar (FP1) region. However, in some channels over the frontal lobe, we also observed significant correlations between the HbO2 and systemic variables

Dissolved Organic Matter Dynamics in the Oligo/Meso-Haline Zone of Wetland-Influenced Coastal Rivers

Wetlands are key components in the global carbon cycle and export significant amounts of terrestrial carbon to the coastal oceans in the form of dissolved organic carbon (DOC). Conservative behavior along the salinity gradient of DOC and chromophoric dissolved organic matter (CDOM) has often been observed in estuaries from their freshwater end-member (salinity = 0) to the ocean (salinity = 35). While the oligo/meso-haline (salinity \u3c 10) tidal zone of upper estuaries has been suggested to be more complex and locally influenced by geomorphological and hydrological features, the environmental dynamics of dissolved organic matter (DOM) and the environmental drivers controlling its source, transport, and fate have scarcely been evaluated. Here, we investigated the distribution patterns of DOC and CDOM optical properties determined by UV absorbance at 254 nm (A254) and excitation–emission matrix (EEM) fluorescence coupled with parallel factor analysis (PARAFAC) along the lower salinity range (salinity \u3c 10) of the oligo/meso-haline zone for three distinct wetland-influenced rivers; namely the Bekanbeushi River, a cool-temperate river with estuarine lake in Hokkaido, Japan, the Harney River, a subtropical river with tidally-submerged mangrove fringe in Florida, USA, and the Judan River, a small, acidic, tropical rainforest river in Borneo, Malaysia. For the first two rivers, a clear decoupling between DOC and A254 was observed, while these parameters showed similar conservative behavior for the third. Three distinct EEM-PARAFAC models established for each of the rivers provided similar spectroscopic characteristics except for some unique fluorescence features observed for the Judan River. The distribution patterns of PARAFAC components suggested that the inputs from plankton and/or submerged aquatic vegetation can be important in the Bekanbeushi River. Further, DOM photo-products formed in the estuarine lake were also found to be transported upstream. In the Harney River, whereas upriver-derived terrestrial humic-like components were mostly distributed conservatively, some of these components were also derived from mangrove inputs in the oligo/meso-haline zone. Interestingly, fluorescence intensities of some terrestrial humic-like components increased with salinity for the Judan River possibly due to changes in the dissociation state of acidic functional groups and/or increase in the fluorescence quantum yield along the salinity gradient. The protein-like and microbial humic-like components were distributed differently between three wetland rivers, implying that interplay between loss to microbial degradation and inputs from diverse sources are different for the three wetland-influenced rivers. The results presented here indicate that upper estuarine oligo/meso-haline regions of coastal wetland rivers are highly dynamic with regard to the biogeochemical behavior of DOM

Born Effective Charges and Infrared Response of LiBC

Calculations of the zone center optical mode frequencies (including LO-TO splitting), Born effective charges Z$^*_{\alpha\alpha}$ for each atom, dielectric constants $\epsilon_{0}$ and $\epsilon_{\infty}$, and the dielectric response in the infrared, using density functional linear response theory, are reported. Calculated Raman modes are in excellent agreement with experimental values (170 cm$^{-1}$ and 1170 cm$^{-1}$), while it will require better experimental data to clarify the infrared active mode frequencies. The Born effective charges Z$^*_{\alpha \alpha}$ (i) have surprisingly different values for B and C, and (ii) show considerable anisotropy. Relationships between the effective charges and LO-TO splitting are discussed, and the predicted reflectivity in the range 0 -- 1400 cm$^{-1}$ is presented. These results hold possible implications for Li removal in LiBC, and C substition for B in MgB$_2$.Comment: 6 pages, 3 figure

Sodium and chloride channelopathies with myositis:Coincidence or connection?

Introduction: A proximal myopathy develops in some patients with muscle channelopathies, but the causative molecular mechanisms are unknown. Methods: We reviewed retrospectively all clinical and muscle biopsy findings of 3 patients with channelopathy and additional myositis. Direct DNA sequencing was performed. Results: Pathogenic mutations were identified in each case. Biopsies demonstrated inflammatory infiltrates. Conclusions: Clinicians should consider muscle biopsy in channelopathy patients with severe myalgia and/or subacute weakness and accompanying elevated creatine kinase. Chance association of myositis and channelopathy is statistically unlikely. An alternative hypothesis suggests that inflammatory insults could contribute to myopathy in some patients. Muscle Nerve 44: 283-288, 201