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High-resolution maps of magnetization transfer with inherent correction for RF inhomogeneity and T1 relaxation obtained from 3D FLASH MRI

An empirical equation for the magnetization transfer (MT) FLASH signal is derived by analogy to dual-excitation FLASH, introducing a novel semiquantitative parameter for MT, the percentage saturation imposed by one MT pulse during TR. This parameter is obtained by a linear transformation of the inverse signal, using two reference experiments of proton density and T1 weighting. The influence of seq

Secretion of ghrelin from rat stomach ghrelin cells in response to local microinfusion of candidate messenger compounds: A microdialysis study

Ghrelin is produced by A-like cells (ghrelin cells) in the mucosa of the acid-producing part of the stomach. The mobilization of ghrelin is stimulated by nutritional deficiency and suppressed by nutritional abundance. In an attempt to identify neurotransmitters and regulatory peptides that may contribute to the physiological, nutrient-related regulation of ghrelin secretion, we challenged the ghre

Reactivity of triruthenium thiophyne and furyne clusters: competitive S-C and P-C bond cleavage reactions and the generation of highly unsymmetrical alkyne ligands

The synthesis and reactivity of the thiophyne and furyne clusters [Ru-3(CO)(7)(mu-dppm)(mu(3)-eta(2)-C4H2E){mu-P(C4H3E)(2)}(mu-H)] (E = S, O) is reported. Addition of P(C4H3E)(3) to [Ru-3(CO)(10)(mu-dppm)] (1) at room temperature in the presence of Me3NO gives simple substitution products [Ru-3(CO)(9)(mu-dppm)-P(C4H3E)(3)}] (E = S, 2; E = O, 3). Mild thermolysis in the presence of further Me3NO af

Effects of antioxidant pretreatment on the survival of embryonic dopaminergic neurons in vitro and following grafting in an animal model of Parkinson's disease

The effect of pretreating cell suspensions of embryonic rat ventral mesencephala (VM) with antioxidant combinations on the survival of dopaminergic (DA) neurons was studied in vitro and following transplantation into the unilateral 6-hydroxydopamine (6-OHDA)-lesioned rat model of Parkinson's disease. The in vitro experiments examined the effects of two thiol antioxidants, N-acetyl-L-cysteine (NAC)

Reaction mechanism of transmetalation between tetraorganostannanes and platinum(II) aryltriflate complexes. Mechanistic model for stille couplings

The complexes trans-[PtPh(OTf)(PMe2Ph)(2)] (1) and trans- [PtPh(OTf)(PPh3)(2)] (4) were synthesized from the corresponding chloro complexes in moderate yields. Complex I is slowly hydrolyzed in solution, giving the dinuclear hydroxo-bridged complex [Pt(mu-OH)(PMe2Ph)(2)](2)(CF3SO3)(2) (6), which was characterized by X-ray crystallography. In solution I and 4 undergo fast solvolysis to give the cor

What do lateralized displays tell us about visual word perception? A cautionary indication from the word-letter effect

A common assumption underlying laterality research is that visual field asymmetries in lateralized word perception indicate the hemispheric specialisation of processes generally available for the perception of words, including words viewed in a more typical setting (i.e. in the central visual field). We tested the validity of this assumption using a phenomenon (the word-letter effect) frequently r

A study on sampling methods for chloride profiles – simulations using data from EPMA

Abstract in French La de´termination du profil de concentration en chlorures dans un be´ton d’une structure soumise a` un environnement marin est une de´marche usuelle pour une pre´diction de la dure´e de service re´siduelle de la structure. Les me´thodes d’e´chantillonnage les plus communes sont le pre´le`vement de poudre par forage ou le carottage a` sec a` profondeurs croissantes pour dosages dInvestigating marine concrete by determining the chloride profile is a common way for making a prediction of the remaining service life of a structure. The most common methods of sampling concrete for this purpose is dust sampling by dry drilling or sampling cores which are analyzed by profile grinding in a laboratory. Now, a similar study has been performed, by simulating different sampling techn

MiniReview: Bioinformatic study of bile responses in Campylobacterales

Campylobacter, Helicobacter and Wolinella are genera of the order Campylobacterales, belonging to the class Epsilonproteobacteria. Their habitats are various niches in the gastrointestinal tract of higher animals, where they may come into contact with bile. Microorganisms in these environments require mechanisms of resistance to the surface-active amphipathic molecules with potent antimicrobial ac

3-Hydroxy fatty acids in saliva as diagnostic markers in chronic periodontitis

Saturated straight- and branched-chain 3-hydroxy fatty acids (3-OH FAs) of 10-18 carbon chain lengths were determined in saliva from 27 individuals with chronic periodontitis and 18 healthy individuals by using gas chromatography-tandem mass spectrometry. Of the 14 different 3-OH FAs detected, 3-OH-C-i17:0 was the most abundant in the periodontitis samples while 3-OH-C-14:0 was the most abundant i

40Ar/39Ar biotite and hornblende geochronology from the Oskarshamn area, SE Sweden: Discerning multiple Proterozoic tectonothermal events

Twelve 40Ar-39Ar biotite and four hornblende age determinations have been carried out to constrain the cooling history of the Proterozoic bedrock near Oskarshamn, SE Sweden; an area identified as a possible site for long-term nuclear waste storage. The bedrock hosts 1.80 Ga granites, granodiorites, quartz monzodiorites and diorites/gabbros of the Transscandinavian Igneous Belt and two 1.45-1.44 Ga

A coupled human-environment model for desertification simulation and impact studies

This paper presents the development of a system dynamic model to simulate and analyze desertification. The human-environment coupled model integrates socio-economic drivers with bio-physical drivers of biomass production, land degradation and desertification. It is based on the UN and GEF definitions of desertification. It illustrates the concept of desertification through differential equation an

Cereal fiber intake may reduce risk of gastric adenocarcinomas: The EPIC-EURGAST study

Numerous case-control studies suggest dietary fiber may reduce risk of gastric cancer, but this has not been confirmed prospectively. A previous case-control study reported reduced risk of gastric cardia adenocarcinomas associated with cereal fiber, but not with fruit or vegetable fiber. To date, different food sources of fiber have not been examined with respect to noncardia tumors or diverse his

Radiographic wear assessment in a total knee prosthesis. 5- to 9-year follow-up study of 158 knees

One hundred fifty-eight Porous-Coated Anatomic (Howmedica, Rutherford, NJ) primary total knee prostheses were evaluated clinically and radiographically to measure the remaining thickness of the plastic insert. Anteroposterior radiographs were taken with the beam guided parallel to the tibial plate by a fluoroscope. The knees were forced into varus and valgus, and the heights of the medial and late

The S3 State of the Oxygen-Evolving Complex in Photosystem II Is Converted to the S2YZ State at Alkaline pH

Here we report an EPR signal that is induced by a pH jump to alkaline pH in the S3 state of the oxygen-evolving complex in photosystem II. The S3 state is first formed with two flashes at pH 6. Thereafter, the pH is changed in the dark prior to freezing of the sample. The EPR signal is 90-100 G wide and centered around g = 2. The signal is reversibly induced with a pK = 8.5 ± 0.3 and is very stabl

Stratigraphy of peatlands in central and northern Sweden: evidence of Holocene climatic change and peat accumulation

Early peat surveys demonstrated the potential to detect Holocene climatic changes in southern Sweden through analysis of the degree of decomposition of Sphagnum peat and motivated systematic collection of peat-strati graphic information during subsequent geological mappings in central and northern Sweden. The resulting (published and unpublished) data was compiled and reanalysed, taking into accou

What Makes Therapy Work? A Multifaceted Question.

The question "what makes therapy work?" has many facets. For instance, if there is evidence for a certain form of psychotherapy, one must question whether the positive effects are due to its methods or rather to "common factors" that may be shared with a number of other procedures. Second, because all evidence-based forms of psychotherapy represent treatment packages that involve a large number of