Altered intrinsic functional coupling between core neurocognitive networks in Parkinson\u27s disease

Parkinson3s disease (PD) is largely attributed to disruptions in the nigrostriatal dopamine system. These neurodegenerative changes may also have a more global effect on intrinsic brain organization at the cortical level. Functional brain connectivity between neurocognitive systems related to cognitive processing is critical for effective neural communication, and is disrupted across neurological disorders. Three core neurocognitive networks have been established as playing a critical role in the pathophysiology of many neurological disorders: the default-mode network (DMN), the salience network (SN), and the central executive network (CEN). In healthy adults, DMN–CEN interactions are anti-correlated while SN–CEN interactions are strongly positively correlated even at rest, when individuals are not engaging in any task. These intrinsic between-network interactions at rest are necessary for efficient suppression of the DMN and activation of the CEN during a range of cognitive tasks. To identify whether these network interactions are disrupted in individuals with PD, we used resting state functional magnetic resonance imaging (rsfMRI) to compare between-network connectivity between 24 PD participants and 20 age-matched controls (MC). In comparison to the MC, individuals with PD showed significantly less SN–CEN coupling and greater DMN–CEN coupling during rest. Disease severity, an index of striatal dysfunction, was related to reduced functional coupling between the striatum and SN. These results demonstrate that individuals with PD have a dysfunctional pattern of interaction between core neurocognitive networks compared to what is found in healthy individuals, and that interaction between the SN and the striatum is even more profoundly disrupted in those with greater disease severity

Observations on Mass Mortalities of the Sooty Eel, Bascanichthys bascanium, and the Speckled Worm Eel, Myrophis punctatus, Associated With a Fish Kill in the Mississippi Sound

Mass mortalities of the sooty eel, Bascanichthys bascanium, and the speckled worm eel, Myrophis punctatus, were observed in association with a fish kill which occurred the morning of 18 June 1994 on the south shore of Deer Island, a nearshore barrier island located off Biloxi, Mississippi. B. bascanium and M. punctatus, as well as other fishes, were found dead and dying near the shore in reddish-brown water and along a lengthy stretch of fringing sandy beach. Both species of eels are infrequently reported from Mississippi waters but were the most abundant fishes recorded from the kill. A visual census conducted along ~1.6 km of shoreline and partially submerged tidal flat estimated eel mortalities at 8,000 individuals. The presence of highly discolored water and the lethargic behavior displayed by live eels and other fishes at the site of the kill suggested the episode may have been related to a localized phytoplankton bloom

Developing Ecological Criteria for Prescribed Fire in South Florida Pine Rockland Ecosystems

The pine rocklands of South Florida, characterized by a rich herbaceous flora with many narrowly endemic taxa beneath an overstory of south Florida slash pine (Pinus elliottii var. densa), are found in three areas: the Miami Rock Ridge of southeastern peninsular Florida, the Lower Florida Keys, and slightly elevated portions of the southern Big Cypress National Preserve. Fire is an important element in these ecosystems, since in its absence the pine canopy is likely to be replaced by dense hardwoods, resulting in loss of the characteristic pineland herb flora. Prescribed fire has been used in Florida Keys pine forests since the creation of the National Key Deer Refuge (NKDR), with the primary aim of reducing fuels. Because fire can also be an effective tool in shaping ecological communities, we conducted a 4-year research study which explored a range of fire management options in NKDR. The intent of the study was to provide the Fish and Wildlife Service and other land managers with information regarding when and where to burn in order to perpetuate these unique forests

Studies on the Weak Itinerant Ferromagnet SrRuO3 under High Pressure to 34 GPa

The dependence of the Curie temperature Tc on nearly hydrostatic pressure has been determined to 17.2 GPa for the weak itinerant ferromagnetic SrRuO3 in both polycrystalline and single-crystalline form. Tc is found to decrease under pressure from 162 K to 42.7 K at 17.2 GPa in nearly linear fashion at the rate dTc/dP = -6.8 K/GPa. No superconductivity was found above 4 K in the pressure range 17 to 34 GPa. Room-temperature X-ray diffraction studies to 25.3 GPa reveal no structural phase transition but indicate that the average Ru-O-Ru bond angle passes through a minimum near 15 GPa. The bulk modulus and its pressure derivative were determined to be B =192(3) GPa and B' = 5.0(3), respectively. Parallel ac susceptibility studies on polycrystalline CaRuO3 at 6 and 8 GPa pressure found no evidence for either ferromagnetism or superconductivity above 4 K

A model for chloroplast thylakoid membranes involving orderly arrangements of negatively charged lipidic particles containing sulphoquinovosyldiacylglycerol

AbstractAddition of sulphoquinivosyldiacylglycerol (SL) to mixtures of monogalactosyldiacylglycerol (MG) and digalactosyldiacylglycerol (DG) induces the appearance of paracrystalline arrays of 80–100 Å lipidic particles. The hypothesis is presented that SL occupies the position in the leaflet opposite the micelle of MG or the position in the leaflet on the convex side of the bulge or cusp in the corresponding model for lipidic particles, and that these orderly arranged lipidic particles containing negatively charged SL may form part of the basis for the orderly arrangement of other molecules functioning in photosyntesis in the thylakoid membrane

Tree Mortality following Prescribed Fire and a Storm Surge Event in Slash Pine (Pinus elliottii var. densa) Forests in the Florida Keys, USA

In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated with tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase

Liver Development, Regeneration, and Carcinogenesis

The identification of putative liver stem cells has brought closer the previously separate fields of liver development, regeneration, and carcinogenesis. Significant overlaps in the regulation of these processes are now being described. For example, studies in embryonic liver development have already provided the basis for directed differentiation of human embryonic stem cells and induced pluripotent stem cells into hepatocyte-like cells. As a result, the understanding of the cell biology of proliferation and differentiation in the liver has been improved. This knowledge can be used to improve the function of hepatocyte-like cells for drug testing, bioartificial livers, and transplantation. In parallel, the mechanisms regulating cancer cell biology are now clearer, providing fertile soil for novel therapeutic approaches. Recognition of the relationships between development, regeneration, and carcinogenesis, and the increasing evidence for the role of stem cells in all of these areas, has sparked fresh enthusiasm in understanding the underlying molecular mechanisms and has led to new targeted therapies for liver cirrhosis and primary liver cancers

Effective field theory calculation of second post-Newtonian binary dynamics

We use the effective field theory for gravitational bound states, proposed by Goldberger and Rothstein, to compute the interaction Lagrangian of a binary system at the second Post-Newtonian order. Throughout the calculation, we use a metric parametrization based on a temporal Kaluza-Klein decomposition and test the claim by Kol and Smolkin that this parametrization provides important calculational advantages. We demonstrate how to use the effective field theory method efficiently in precision calculations, and we reproduce known results for the second Post-Newtonian order equations of motion in harmonic gauge in a straightforward manner.Comment: Replaced with published versio

GreatO+ Supplementation Leads to Greater Proportions of Omega-3 Fatty Acids in the Small Intestines of Holstein Steers

Objective:This study aimed to determine if supplementation of GreatO+, an extruded blend of flaxseed and microalgae (NBO3, Manhattan, KS), in Holstein steers would lead to greater amounts of fatty acids, particularly omega-3s, in the small intestines. Study Description:This study utilized 12 cannulated Holstein steers assigned to two treatments: with or without supplementation of GreatO+as a source of omega-3 fatty acids. Two periods were utilized, consisting of a 15-day adaptation interval and a four-day collection interval. After the end of the collection period, each steer was transitioned to the other treatment for the second period. This study was conducted at the Kansas State Intake Facility, equipped with automated feed and water troughs. The Bottom Line:Cattle supplemented with GreatO+have greater amounts of omega-3 fatty acid available for absorption in the small intestines