bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intrastriatal convection-enhanced delivery results in widespread perivascular distribution in a pre-clinical model
Authors: Barua Neil U , Bienemann Alison S , Hesketh Shirley , Wyatt Marcella J , Castrique Emma , Love Seth , Gill Steven S 
Published: January 2012

Abstract

Background
Convection-enhanced delivery (CED), a direct method for drug delivery to the brain through intraparenchymal microcatheters, is a promising strategy for intracerebral pharmacological therapy. By establishing a pressure gradient at the tip of the catheter, drugs can be delivered in uniform concentration throughout a large volume of interstitial fluid. However, the variables affecting perivascular distribution of drugs delivered by CED are not fully understood. The aim of this study was to determine whether the perivascular distribution of solutes delivered by CED into the striatum of rats is affected by the molecular weight of the infused agent, by co-infusion of vasodilator, alteration of infusion rates or use of a ramping regime. We also wanted to make a preliminary comparison of the distribution of solutes with that of nanoparticles.

Methods
We analysed the perivascular distribution of 4, 10, 20, 70, 150 kDa fluorescein-labelled dextran and fluorescent nanoparticles at 10 min and 3 h following CED into rat striatum. We investigated the effect of local vasodilatation, slow infusion rates and ramping on the perivascular distribution of solutes. Co-localisation with perivascular basement membranes and vascular endothelial cells was identified by immunohistochemistry. The uptake of infusates by perivascular macrophages was quantified using stereological methods.

Results
Widespread perivascular distribution and macrophage uptake of fluorescein-labelled dextran was visible 10 min after cessation of CED irrespective of molecular weight. However, a significantly higher proportion of perivascular macrophages had taken up 4, 10 and 20 kDa fluorescein-labelled dextran than 150 kDa dextran (p < 0.05, ANOVA). Co-infusion with vasodilator, slow infusion rates and use of a ramping regime did not alter the perivascular distribution. CED of fluorescent nanoparticles indicated that particles co-localise with perivascular basement membranes throughout the striatum but, unlike soluble dextrans, are not taken up by perivascular macrophages after 3 h.

Conclusions
This study suggests that widespread perivascular distribution and interaction with perivascular macrophages is likely to be an inevitable consequence of CED of solutes. The potential consequences of perivascular distribution of therapeutic agents, and in particular cytotoxic chemotherapies, delivered by CED must be carefully considered to ensure safe and effective translation to clinical trials.
Desiccation induces viable but Non-Culturable cells in Sinorhizobium meliloti 1021
Authors: Vriezen Jan AC , de Bruijn Frans J , Nüsslein Klaus R 
Published: January 2012

Abstract

Sinorhizobium meliloti is a microorganism commercially used in the production of e.g. Medicago sativa seed inocula. Many inocula are powder-based and production includes a drying step. Although S. meliloti survives drying well, the quality of the inocula is reduced during this process. In this study we determined survival during desiccation of the commercial strains 102F84 and 102F85 as well as the model strain USDA1021.
The survival of S. meliloti 1021 was estimated during nine weeks at 22% relative humidity. We found that after an initial rapid decline of colony forming units, the decline slowed to a steady 10-fold reduction in colony forming units every 22 days. In spite of the reduction in colony forming units, the fraction of the population identified as viable (42-54%) based on the Baclight live/dead stain did not change significantly over time. This change in the ability of viable cells to form colonies shows (i) an underestimation of the survival of rhizobial cells using plating methods, and that (ii) in a part of the population desiccation induces a Viable But Non Culturable (VBNC)-like state, which has not been reported before. Resuscitation attempts did not lead to a higher recovery of colony forming units indicating the VBNC state is stable under the conditions tested. This observation has important consequences for the use of rhizobia. Finding methods to resuscitate this fraction may increase the quality of powder-based seed inocula.
99mTc-MAG3 scintigraphy for the longitudinal follow-up of kidney function in a mouse model of renal ischemia-reperfusion injury
Authors: Herrler Tanja , Wang Hao , Tischer Anne , Bartenstein Peter , Jauch Karl-Walter , Guba Markus , Diemling Markus , Nimmon Cyril , Hacker Marcus 
Published: January 2012

Abstract

Background
Experimental models are essential tools in the development and evaluation of novel treatment options, but the preclinical model of renal ischemia-reperfusion injury is limited to the retrieval of (very) early functional data, leaving the pivotal long-term outcome unknown. The present study applies technetium-99m-mercapto-acetyl-tri-glycine [99mTc-MAG3] scintigraphy for the longitudinal follow-up examination of long-term kidney function after renal ischemia-reperfusion injury.

Methods
Unilateral warm ischemia was induced in scid beige mice by vascular clamping of the kidney hilum for 40 min. 99mTc-MAG3 scintigraphy was performed prior to injury, 8 and 14 days post ischemia. The fractional uptake rate [FUR] was calculated from scintigraphy data as a measure of renal clearance.

Results
FUR demonstrated a significant functional impairment of the ischemic kidney 8 and 14 days after injury (P < 0.05 vs. baseline), while contralateral non-ischemic kidneys showed no significant changes. In histological analysis, ischemic kidneys exhibited tubular dilatation and cytoplasmic degeneration as signs of hypoxia without any evidence for necrosis.

Conclusions
FUR enables the detection of renal dysfunction and longitudinal long-term follow-up examination in the same individual. Our model may facilitate preclinical therapy evaluation for the identification of effective renoprotective therapies.
Profiles of Receptive and Expressive Language Abilities in Boys With Comorbid Fragile X Syndrome and Autism
Authors: McDuffie Andrea , Kover Sara , Abbeduto Leonard , Lewis Pamela , Brown Ted 
Published: January 2012

Abstract
The authors examined receptive and expressive language profiles for a group of verbal male children and adolescents who had fragile X syndrome along with varying degrees of autism symptoms. A categorical approach for assigning autism diagnostic classification, based on the combined use of the Autism Diagnostic Interview—Revised and the Autism Diagnostic Observation Schedule (ADOS), and a continuous approach for representing autism symptom severity, based on ADOS severity scores, were used in 2 separate sets of analyses. All analyses controlled for nonverbal IQ and chronological age. Nonverbal IQ accounted for significant variance in all language outcomes with large effect sizes. Results of the categorical analyses failed to reveal an effect of diagnostic group (fragile X syndrome–autism, fragile X syndrome–no autism) on standardized language test performance. Results of the continuous analyses revealed a negative relationship between autism symptom severity and all of the standardized language measures. Implications for representing autism symptoms in fragile X syndrome research are considered.
Grazing-angle Incidence X-ray Diffraction by the Si1-α(x)-β(x)Geβ(x)Cβ(x)/Si Heterojunction where the Germanium and the Carbon Concentrations are Periodically Varying along the Flat Layer Surface
Authors: Bezirganyan Hayk H. , Bezirganyan Siranush E. , Bezirganyan Hakob P. , Bezirganyan Petros H. 
Published: January 2012

AbstractPresented theoretical paper concerns the investigation of SiGeC/Si heterojunction by the Grazing-angle Incidence X-ray Diffraction (GIXD) method. We consider a possibility in principal of the GIXD by the specific long-range harmonic variations of the germanium and carbon compositions in the thin SiGeC layer. Evaluation of the theoretically calculated coherent part of x-radiation scattered by the SiGeC layer points the way to the experimental direct investigations of the long-period structured intermediate transformation states of SiGeC layer that emerge owing to inhomogeneity of the strain field along the heterojunction surface.
On properties of (weakly) small groups
Authors: Milliet Cédric 
Published: January 2012

AbstractA group is small if it has only countably many completen-types over the empty set for each natural numbern. More generally, a groupGis weakly small if it has only countably many complete 1-types over every finite subset ofG. We show here that in a weakly small group, subgroups which are definable with parameters lying in a finitely generated algebraic closure satisfy the descending chain conditions for their traces in any finitely generated algebraic closure. An infinite weakly small group has an infinite abelian subgroup, which may not be definable. A small nilpotent group is the central product of a definable divisible group with a definable one of bounded exponent. In a group with simple theory, any set of pairwise commuting elements is contained in a definable finite-by-abelian subgroup. First corollary: a weakly small group with simple theory has an infinite definable finite-by-abelian subgroup. Secondly, in a group with simple theory, a solvable groupAof derived lengthnis contained in anA-definable almost solvable group of class at most 2n– 1.
Cardinal invariants of monotone and porous sets
Authors: Hrušák Michael , Zindulka Ondřej 
Published: January 2012

AbstractA metric space (X, d) ismonotoneif there is a linear order < onXand a constantcsuch thatd(x, y)≤c d(x, z)for allx<y<zinX. We investigate cardinal invariants of theσ-idealMongenerated by monotone subsets of the plane. Since there is a strong connection between monotone sets in the plane and porous subsets of the line, plane and the Cantor set, cardinal invariants of these ideals are also investigated. In particular, we show that non(Mon) ≥mσ-linked, but non(Mon) <mσ-centeredis consistent. Also cov(Mon) <cand cof (N) < cov(Mon) are consistent.
Social Identification and Differences in External and Internal Auditor Objectivity
Authors: Stefaniak Chad M. , Cornell Robert M. 
Published: January 2012

SUMMARY
Stefaniak et al.'s (2012) paper, “The Effects of Organizational Identification on Internal and External Auditors' Evaluation of Internal Control Deficiencies,” investigates how the relationships that internal (external) auditors form with their employers (audit clients) influence their objectivity. Stefaniak et al. (2012) found, in a case concerning an internal control issue, that when internal auditors are more attached to their employers, they are more conservative when control issues. Conversely, when external auditors are more attached to their audit clients, they are more lenient. The primary implication is that external auditors' reliance on internal auditors' work, as suggested by Auditing Standard No. 5, could yield an overall positive effect on audit efficiency and perhaps even effectiveness.
A Note on General Classification of Motions in a Baroclinic Atmosphere
Authors: Monin A. S. , Obukhov A. M. 
Published: January 2012

In the present note we make an attempt to classify the basic types of dynamical processes in the atmosphere such as gravitational and acoustic waves and horizontal eddy motions by solving the problem of small oscillations in the baroclinic atmosphere.
We have found a certain invariant with the help of which one can estimate the final stationary state of the atmosphere under arbitrary conditions without the analysis of the wave processes which cause the field change. The most natural way of obtaining the special equations for the numerical forecasting is that of computing the first derivative in time of the invariant in the second approximation (quadratic terms being taken into account).
The filtrating role of the quasi-static approximation is being investigated in the note. Quasi-static approximation filtrates the internal acoustic waves and somewhat increases the frequencies of the gravitational waves.
It has, in particular, been shown that the time required for establishing the quasi-static balance in the atmosphere is equal to some minutes.
On the Problem of Initial Data for the Primitive Equations
Authors: Phillips Norman A. 
Published: January 2012

It is first demonstrated that in a forecast with the primitive equations, pure geostrophic or purely non-divergent initial wind fields will result in noticeable meteorological “noise”, especially in a baroclinic atmosphere. It is then shown in a linear example that this noise is greatly suppressed if the divergence of the initial wind field is set equal to the divergence implied by the usual geostrophic theory of numerical weather prediction. The absence of noise in Charney’s 1955 test computation with non-divergent “balanced” initial data is explained.
Finally, the quasi-geostrophic expansion is used to define initial data for a non-linear forecast with the primitive equations. Two cases are considered, that where only the geopotential is known from observations, and that where only the non-divergent part of the wind is known from observation. It is shown that the initial tendencies computed from initial data of this kind preserve the assumed geostrophic character of the flow, and thereby make it possible to get more accurate forecasts with the primitive equations.
Radiance Distribution in the Upper Layers of the Sea
Authors: Jerlov N. G. , Fukuda M. 
Published: January 2012

The angular distribution of underwater radiance for green light has been studied in the upper turbid layers of the Gullmar fjord by means of a radiance meter which is lowered in the sea along a guide wire with a fixed orientation. A theoretical discussion considers the different components entering into the light field, viz. direct sunlight, skylight, and scattered light. On the basis of available measurements of the volume scattering function the scattered light is evaluated by integrating light scattered from the predominant sun beam alone. The experimental angular distributions of radiance compare well with the theoretical distributions. In particular it is demonstrated that the radiance in the angle interval ± 45° from the sun attains a maximum below the surface.
Some Aspects of Hurricane Daisy, 1958
Authors: Riehl Herbert , Malkus Joanne 
Published: January 2012

Observations from research flight missions into hurricane Daisy (1958) are utilized to compute the budgets of heat, moisture, kinetic energy, and momentum. Calculations are performed for a period when the cyclone was just becoming a hurricane, and for a second period, two days later, when it had attained maturity.
The level of non-divergence separating lower inflow from upper outflow was quite high, near 500 mb. Mass flow increased considerably between the two days, but rainfall remained quite moderate for a severe hurricane. The radiation heat sink was small compared to the oceanic source so that the system was “open” within the confines of the study. If all ascent took place in the hard radar echoes, the mean vertical speed there was about 7 meters per sec. Without such localized ascent, heat balance could not be achieved. Heat budget computations permitted assessing the fraction of mass flow reaching upper levels in undilute “hot” cumulonimbus towers and estimation of the number of such towers required, to compare with previous photographic studies. Hot towers proved to be the dominant mechanism of raising warm air to upper levels, particularly in the inner core. However, because of the high level of nondivergence the constraint known as ventilation was active. It is shown not to have been a severe deterrent upon Daisy, nor was it the reason she did not become an extreme storm.
Kinetic energy balance is obtained readily on the first day. Import of kinetic energy through the outermost radius was small, so that most of the energy dissipated in the interior was also produced there by the pressure forces. Ground and internal friction were about equal. The kinetic energy source shifted outward as the storm grew, so that on the day of maturity large inward transport took place. The internal source also increased but wind speeds failed to rise correspondingly. Hence ground friction was inadequate to balance production plus import, and large internal dissipation had to be invoked. This dissipation must be assigned largely to vertical eddies. If ascribed to horizontal eddies, the coefficient of lateral exchange becomes so large that momentum budget requirements cannot be fulfilled by a large amount.
It is concluded from the study that the important mechanisms of the hurricane core can be well represented in a two-dimensional framework, provided the essential effects of the buoyant cumulonimbus towers are properly introduced or parameterized therein. The two-dimensional flow 06 mass is shown in relation to the fields of heat, momentum, and vorticity. The law of conservation of potential vorticity appears to be well satisfied along the stream tubes of the mean motion.
Penetrative convection in stably stratified fluids
Authors: Saunders Peter M. 
Published: January 2012

The downward convection of discrete masses of heavy fluid, called thermals, in a gravitationally stable environment is studied experimentally. For simplicity the ambient stratification is chosen to have a discontinuous two-layer structure with fluid of uniform density in each layer. When released into the homogeneous upper layer the thermal acquires the circulation of a turbulent ring vortex as reported earlier. For weak stratifications, which are however capable of halting the thermal, this circulation is destroyed in a dramatic fashion during the penetration of the lower layer; restoring buoyancy forces then develop a reversed circulation as the thermal flattens and spreads. For strong stratifications no reversal of the circulation occurs, rather the flattening and spreading of the thermal is associated with a gradual decay of the original circulation.
A dimensional argument is proposed to indicate the parameters which determine the extreme penetration of the thermal into the lower layer: this is confirmed by experiment.
In order to generalize the results to more realistic geophysical cases a mechanistic description of thermal behaviour is put forward. The treatment is shown to rationalize the data for environments with (a) neutral stratification, (b) a discontinuous two-layer structure and (c) constant density gradient. Thermal behaviour in a stratification consisting of (a) surmounted by (c) is then predicted.
Observations made by the author of the penetration of tall cumulus clouds into the sub-tropical stratosphere permit a test of the applicability of this model in one geophysical area. For every 1 km of penetration it is deduced that convective motions have an average vertical intensity of 10 m/sec: this prediction is shown to be in good agreement with the limited observational data.
On truncation errors due to vertical differences in various numerical prediction models
Authors: Wiin-Nielsen A. 
Published: January 2012

Some estimates of truncation errors due to vertical finite differences are given. The truncation errors amount to at most 10 % in the phase-speed of the basic mode in a model atmosphere in which the vertical shear of the basic, zonal flow vanishes. An increase of the vertical resolution results in rapidly decreasing truncation errors in this case.
In a model atmosphere, in which the vertical windshear is different from zero, and the static stability parameter is a function of pressure, we find small truncation errors in the initial displacement of the wave, but large errors in the initial amplification.
The initial development of a baroclinic wave is evaluated in three different baroclinic models. The models differ only in the vertical variation of the static stability parameter which is a simple function of pressure in the first model, a constant in the next and zero in the third model. It is shown that the vertical variation of static stability is important for the amplification and the slope of the wave in the vertical direction.
The initial change of the kinetic energy in the models is computed as a function of wave-length. It is shown that the change of kinetic energy is larger in the models where the static stability parameter is constant or zero than in the models where it varies with pressure.
The last section contains some comments on the upper boundary condition. It is shown that the conditions ω = 0 and ϕ < ∞ (ϕ = geopotential) at the upper boundary are equivalent in certain problems.
An entraining jet model for cumulo-nimbus updraughts
Authors: Squireas P. , Turner J. S. 
Published: January 2012

A model of a cumulo-nimbus updraught is presented, based on a steady-state, turbulent, condensing plume, entraining environmental air according to the simple law that the inflow velocity at any height is proportional to the upward velocity of the plume.
With this model, the shape of the cloud as well as its other properties follow from the dynamics, and cloud development is size-dependent. The virtual temperature excess at cloud base is taken as zero; this seems the only appropriate assumption for a steady-state plume model. The thermodynamical treatment is made with few approximations, and the effect of freezing on the dynamics is included in a simple fashion. Some preliminary calculations result in realistic cloud shapes and reasonable values for the internal properties.
Measurement of small-scale oceanic motions with neutrally-buoyant flloats
Authors: Pochapsky T. E. 
Published: January 2012

The movement of water in the ocean waa studied by following 1 3 motions of instrumented neutrally-buoyant floats. Measurements were made at various depths in the Caribbean Sea and in the Atlantic Ocean several hundred miles east of Bermuda. There was a continuous vertical bobbing of the floats, and two floats at nearly the same depth separated at an uneven rate in time. Near the surface, vertical displacements of approximately 3 m took place during periods of 10 to 30 minutes, and movements of approximately 30 m took place over a period of tens of hours. The slow large-amplitude motions were probably forced by semidiurnal tides in the Caribbean. Vertical movements at depths near 1000 m in both operating areas amounted to approximately 10 m over periods of 1 to 2 hours.
Floats at their equilibrium depths do not faithfully follow the movements of the water environment. An approximate solution is derived for the response of a float to an internal wave. It was found that a resonance causes the float movements to exceed the water displacements at the shorter periods whereas the stiffness of the float tends to keep it from moving in deep water where the density gradient is small.