Protein changes and proteolytic degradation in red and white clover plants subjected to waterlogging

Red (Trifolium pratense L., cv. “Start”) and white clover varieties (Trifolium repens L., cv. “Debut” and cv. “Haifa”) were waterlogged for 14 days and subsequently recovered for the period of 21 days. Physiological and biochemical responses of the clover varieties were distinctive, which suggested different sensitivity toward flooding. The comparative study of morphological and biochemical parameters such as stem length, leaflet area, dry weight, protein content, protein pattern and proteolytic degradation revealed prominent changes under waterlogging conditions. Protease activity in the stressed plants increased significantly, especially in red clover cv. “Start”, which exhibited eightfold higher azocaseinolytic activity compared to the control. Changes in the protein profiles were detected by SDS-PAGE electrophoresis. The specific response of some proteins (Rubisco, Rubisco-binding protein, Rubisco activase, ClpA and ClpP protease subunits) toward the applied stress was assessed by immunoblotting. The results characterized the red clover cultivar “Start” as the most sensitive toward waterlogging, expressing reduced levels of Rubisco large and small subunits, high content of ClpP protease subunits and increased activity of protease isoforms.

Evaluation of Stockpiled Berseem Clover and Brown Midrib Sorghum x Sudangrass as Supplements for Grazed Cornstalks in Beef Cow Wintering Systems

Berseem clover and oats were incorporated into a corncorn- oat/berseem clover rotation in 1994 and 1995. Two cuttings of oat-berseem clover hay were harvested during the summer before forage was allowed to stockpile for winter grazing. In 1995, a brown midrib sorghum x sudangrass hybrid was seeded into a field adjacent to a corn field. After corn grain harvest in 1994 and 1995, Charolais x Angus x Simmental cows in midgestation were allotted to replicated fields containing corn crop residues with no complementary forages at 2.5 acres/cow, or corn crop residues and stockpiled berseem clover (2:1) at 2.5 acres/cow to simultaneously graze, or to a drylot. In 1995, cows were allotted to fields containing corn crop residues and brown midrib sorghum x sudangrass (7:3) at 2.5 acres/cow. Berseem clover had greater concentrations of digestible organic matter and crude protein than corn crop residues at the initiation of grazing, but had a more rapid decrease in digestible organic matter concentration than corn crop residues. Brown midrib sorghum x sudangrass forage also had a higher initial concentration of digestible organic matter, but an equal rate of decrease in digestible organic matter concentration to corn crop residues in ungrazed areas of the field. Cows grazing berseem clover with corn crop residues had greater body condition score increases during the first half of the grazing season than cows grazing corn crop residues without complementary forages. Cows grazing corn crop residues without complementary forages required 2,786 and 1,412 less lb hay per cow than cows maintained in a drylot in 1994 and 1995. In 1994, simultaneous grazing of berseem clover with corn crop residues did not reduce hay feeding more than feeding corn crop residues alone. However, in 1995, grazing berseem clover or brown midrib sorghum x sudangrass with corn crop residues reduced the amount of hay required to maintain cows by 358 and 376 lb hay per cow compared with grazing corn crop residues without complementary forage.

Evaluation of Stockpiled Berseem Clover and Brown Midrib Sorghum x Sudangrass as Supplements for Grazed Cornstalks in Beef Cow Wintering Systems

Berseem clover and oats were incorporated into a corn-oat/berseem clover rotation in 1994-1996. Two cuttings of oat-berseem clover hay were harvested during the summer before forage was stockpiled for winter grazing. In 1995, brown midrib sorghum x sudangrass hybrid was seeded into a field adjacent to a corn field. This was repeated in 1996 with a standard sorghum x sudangrass hybrid. After corn harvest in 1994–1996, Charolais x Angus x Simmental cows and heifers in midgestation were allotted to corn crop residue, corn crop residue-berseem clover, and corn crop residue-sorghum x sudangrass fields at 2.5 acres/cow, or to a drylot. Berseem clover had greater concentration of digestible organic matter and crude protein than corn crop residues. Corn crop residue digestible organic matter concentration was lower than berseem clover and the brown midrib sorghum x sudangrass, but was higher than that of the standard sorghum x sudangrass hybrid in 1996. Cows grazing corn crop residues without complementary forages required an average of 2,374 less lb. hay per cow than cows maintained in a drylot in 1994-1996. In 1994 and 1996, simultaneous grazing of berseem clover with corn crop residues did not reduce hay feeding more than feeding corn crop residues alone, yet did significantly reduce the amount of hay needed in 1995 to maintain cows by 358 and 376 lb. hay per cow compared with grazing corn crop residues without complementary forage.

Use of Stockpiled Berseem Clover as a Supplement for Grazed Corn Crop Residues

In the fall of 1994, mature Charolais cross cows in midgestation were allotted to duplicate 15 acre fields containing corn crop residues or a 2-to-1 mixture of corn crop residues and berseem clover planted in 3 strips at an allowance of 2.5 acres/cow for a 140 day wintering season. Similar cows were allotted duplicate drylots. All cows were fed hay as necessary to maintain a body condition score of 5. Cows grazing corn crop residues with or without berseem clover required 2596 pounds less hay per cow than cows maintained in a drylot. There was no difference in the amounts of hay required by cows grazing corn crop residues alone or with berseem clover. Initial organic matter yield of berseem clover was nearly that of corn crop residues and did not decrease as rapidly as corn crop residues. Berseem clover had a higher organic matter digestibility than corn crop residues at the initiation of grazing. Organic matter digestibility of berseem clover, however, decreased more rapidly than corn crop residues because of weathering during the winter.

Changes in Chemical Composition and Digestion Kinetics of Stockpiled Kura Clover in Late Fall

Stockpiled kura clover samples harvested on three different winter dates were used to determine changes in chemical composition and N digestion kinetics. Kura clover was harvested from four different plots at 14 d intervals and analyzed for neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), acid detergent insoluble nitrogen (ADIN), and in vitro digestible dry matter (IVDMD), and in situ digestion kinetics of N. Crude protein concentrations decreased, but ADIN concentrations increased with later date of harvest. Digestible N pool-size and the rate of digestion was the lowest in third-harvest kura clover. Although the proportion of protein that is soluble or nondigestible increased, proportion of protein that is potentially digestible decreased with maturity.

Sweet Puppies and Cute Babies: Perceptual Adaptation to Babyfacedness Transfers across Species

Infant faces are very salient stimuli. The Kindchenschema describes specific features that characterize a cute infant face. In this study we used a visual adaptation paradigm to investigate the universality of the perceptual properties of the Kindchenschema. In Experiment 1, twenty-four participants adapted to cute and less cute human infant faces and in Experiment 2, twenty-four new participants adapted to cute and less cute faces of puppy dogs. In both experiments the task was to assess the cuteness of subsequently presented human infant faces. The results revealed cuteness after-effects for human infant faces in both adaptation conditions, suggesting a common mechanism coding cuteness in human and non-human faces. This study provides experimental evidence for the universality of the well-described concept of the Kindchenschema.

Giant cellulitis-like Sweet Syndrome, a new variant of neutrophilic dermatosis

BACKGROUND Neutrophilic dermatoses comprise a wide spectrum of inflammatory diseases with overlapping features characterized histologically by the presence of an aseptic neutrophilic infiltrate in the epidermis, dermis, and/or hypodermis and are often associated with systemic inflammatory and neoplastic disorders. OBSERVATIONS We describe 3 patients with an unusual neutrophilic dermatosis characterized by relapsing episodes of fever, widespread infiltrated plaques with bullous appearance, and variable involvement of the arms, legs, abdomen, and/or trunk. Light microscopy studies showed marked edema of the papillary dermis with an inflammatory infiltrate consisting mainly of mature neutrophils. All 3 patients were morbidly obese, and workup revealed underlying cancer in 2 cases: myeloma and breast carcinoma. Management of the underlying disease resulted in long-term remission of the skin disease. CONCLUSIONS The clinicopathologic features in our 3 cases best correspond to a widespread giant cellulitis-like form of Sweet syndrome. Knowledge of this newly observed unusual variant of Sweet syndrome within the broad spectrum of neutrophilic diseases is important for its prompt and proper management.

High-sensitivity rod photoreceptor input to the blue-yellow color opponent pathway in macaque retina.

Small bistratified cells (SBCs) in the primate retina carry a major blue-yellow opponent signal to the brain. We found that SBCs also carry signals from rod photoreceptors, with the same sign as S cone input. SBCs exhibited robust responses under low scotopic conditions. Physiological and anatomical experiments indicated that this rod input arose from the AII amacrine cell-mediated rod pathway. Rod and cone signals were both present in SBCs at mesopic light levels. These findings have three implications. First, more retinal circuits may multiplex rod and cone signals than were previously thought to, efficiently exploiting the limited number of optic nerve fibers. Second, signals from AII amacrine cells may diverge to most or all of the approximately 20 retinal ganglion cell types in the peripheral primate retina. Third, rod input to SBCs may be the substrate for behavioral biases toward perception of blue at mesopic light levels.

Dehydrin expression as a potential diagnostic tool for cold stress in white clover

Cold acclimation is important for crop survival in environments undergoing seasonal low temperatures. It involves the induction of defensive mechanisms including the accumulation of different cryoprotective molecules among which are dehydrins (DHN). Recently several sequences coding for dehydrins were identified in white clover (Trifolium repens). This work aimed to select the most responsive to cold stress DHN analogues in search for cold stress diagnostic markers. The assessment of dehydrin transcript accumulation via RT-PCR and immunodetection performed with three antibodies against the conserved K-, Y-, and S-segment allowed to outline different dehydrin types presented in the tested samples. Both analyses confirmed that YnKn dehydrins were underrepresented in the controls but exposure to low temperature specifically induced their accumulation. Strong immunosignals corresponding to 37–40 kDa with antibodies against Y- and K-segment were revealed in cold-stressed leaves. Another ‘cold-specific’ band at position 52–55 kDa was documented on membranes probed with antibodies against K-segment. Real time RT-qPCR confirmed that low temperatures induced the accumulation of SKn and YnSKn transcripts in leaves and reduced their expression in roots. Results suggest that a YnKn dehydrin transcript with GenBank ID: KC247805 and the immunosignal at 37–40 kDa, obtained with antibodies against Y- and K-segment are reliable markers for cold stress in white clover. The assessment of SKn (GenBank ID: EU846208) and YnSKn (GenBank ID: KC247804) transcript levels in leaves could serve as additional diagnostic tools.

Positive effect of the yellow morph on female reproductive success in the flower colour polymorphic Iris lutescens (Iridaceae), a deceptive species

The deceptive Iris lutescens (Iridaceae) shows a heritable and striking flower colour polymorphism, with both yellow- and purple-flowered individuals growing sympatrically. Deceptive species with flower colour polymorphism are mainly described in the family Orchidaceae and rarely found in other families. To explain the maintenance of flower colour polymorphism in I.lutescens, we investigated female reproductive success in natural populations of southern France, at both population and local scales (within populations). Female reproductive success was positively correlated with yellow morph frequency, at both the population scale and the local scale. Therefore, we failed to observe negative frequency-dependent selection (NFDS), a mechanism commonly invoked to explain flower colour polymorphism in deceptive plant species. Flower size and local flower density could also affect female reproductive success in natural populations. Pollinator behaviour could explain the positive effect of the yellow morph, and our results suggest that flower colour polymorphism might not persist in I.lutescens, but alternative explanations not linked to pollinator behaviour are discussed. In particular, NFDS, although an appealingly simple explanation previously demonstrated in orchids, may not always contribute to maintaining flower colour polymorphism, even in deceptive species.

The role of human-induced fire and sweet chestnut (Castanea sativa Mill.) cultivation on the long-term landscape dynamics of the southern Swiss Alps

Changes in fire occurrence during the last decades in the southern Swiss Alps make knowledge on fire history essential to understand future evolution of the ecosystem composition and functioning. In this context, palaeoecology provides useful insights into processes operating at decadal-to-millennial time scales, such as the response of plant communities to intensified fire disturbances during periods of cultural change. We provide a high-resolution macroscopic charcoal and pollen series from Guèr, a well-dated peat sequence at mid-elevation (832 m.a.s.l.) in southern Switzerland, where the presence of local settlements is documented since the late Bronze Age and the Iron Age. Quantitative fire reconstruction shows that fire activity sharply increased from the Neolithic period (1–3 episodes/1000 year) to the late Bronze and Iron Age (7–9 episodes/1000 year), leading to extensive clearance of the former mixed deciduous forest (Alnus glutinosa, Betula, deciduous Quercus). The increase in anthropogenic pollen indicators (e.g. Cerealia-type, Plantago lanceolata) together with macroscopic charcoal suggests anthropogenic rather than climatic forcing as the main cause of the observed vegetation shift. Fire and controlled burning were extensively used during the late Roman Times and early Middle Ages to promote the introduction and establishment of chestnut (Castanea sativa) stands, which provided an important wood and food supply. Fire occurrence declined markedly (from 9 to 5–6 episodes/1000 year) during late Middle Ages because of fire suppression, biomass removal by human population, and landscape fragmentation. Land-abandonment during the last decades allowed forest to partly re-expand (mainly Alnus glutinosa, Betula) and fire frequency to increase.

Morphological alterations in the liver of yellow perch (Perca flavescens) from a biological mercury hotspot

Mercury (Hg) contamination is a global issue due to its anthropogenic release, long-range transport, and deposition in remote areas. In Kejimkujik National Park and National Historic Site, Nova Scotia, Canada, high concentrations of total mercury (THg) were found in tissues of yellow perch (Perca flavescens). The aim of this study was to evaluate a possible relationship between THg concentrations and the morphology of perch liver as a main site of metal storage and toxicity. Yellow perch were sampled from five lakes known to contain fish representing a wide range in Hg concentrations in fall 2013. The ultrastructure of hepatocytes and the distribution of Hg within the liver parenchyma were analyzed by transmission electron microscopy (TEM) and electron energy loss spectrometry (EELS). The relative area of macrophage aggregates (MAs) in the liver was determined using image analysis software and fluorescence microscopy. No relation between general health indicators (Fulton's condition index) and THg was observed. In line with this, TEM examination of the liver ultrastructure revealed no prominent pathologies related to THg accumulation. However, a morphological parameter that appeared to increase with muscle THg was the relative area of MAs in the liver. The hepatic lysosomes appeared to be enlarged in samples with the highest THg concentrations. Interestingly, EELS analysis revealed that the MAs and hepatic lysosomes contained Hg.

Yellow laser light generation by frequency doubling of the output from a master oscillator fiber power amplifier system

We present a power-scalable approach for yellow laser-light generation based on standard Ytterbium (Yb) doped fibers. To force the cavity to lase at 1154 nm, far above the gain-maximum, measures must be taken to fulfill lasing condition and to suppress competing amplified spontaneous emission (ASE) in the high-gain region. To prove the principle we built a fiber-laser cavity and a fiber-amplifier both at 1154 nm. In between cavity and amplifier we suppressed the ASE by 70 dB using a fiber Bragg grating (FBG) based filter. Finally we demonstrated efficient single pass frequency doubling to 577 nm with a periodically poled lithium niobate crystal (PPLN). With our linearly polarized 1154 nm master oscillator power fiber amplifier (MOFA) system we achieved slope efficiencies of more than 15 % inside the cavity and 24 % with the fiber-amplifier. The frequency doubling followed the predicted optimal efficiency achievable with a PPLN crystal. So far we generated 1.5 W at 1154nm and 90 mW at 577 nm. Our MOFA approach for generation of 1154 nm laser radiation is power-scalable by using multi-stage amplifiers and large mode-area fibers and is therefore very promising for building a high power yellow laser-light source of several tens of Watt.