bluuebunny/crossref_metadata_2025 huggingface dataset:
Coexistence of lactating adenoma and invasive ductal adenocarcinoma of the breast in a pregnant woman
Authors: Saglam A , Can B
Published: December 2004

A 36 year old pregnant woman was admitted to hospital complaining of an enlarging mass in her left breast. Histopathological examination of the mastectomy specimen revealed a high grade infiltrating ductal adenocarcinoma intermixed with a lactating adenoma. Lactating adenomas are rare entities but are the most common masses that occur during pregnancy. Although they are not thought to carry an increased risk of cancer there are two other case reports in the literature of a lactating adenoma associated with an infiltrating carcinoma. In this case, areas where the lactating adenoma and the infiltrating carcinoma were intermixed could be identified. This case could simply be a collision tumour, although the possibility of an invasive carcinoma arising within a lactating adenoma cannot be ruled out. Because of the relative lack of experience with lactating adenomas, the question of an increased association with carcinoma development remains unclear.
Desmoplasia measured by computer assisted image analysis: an independent prognostic marker in colorectal carcinoma
Authors: Sis B , Sarioglu S , Sokmen S , Sakar M , Kupelioglu A , Fuzun M
Published: December 2004

Aims:The assessment of desmoplasia by traditional semiquantitative methods does not provide reliable prognostic data. The aim of this study was to quantify desmoplasia by computerised image analysis in primary colorectal carcinomas and to investigate its ability to predict overall survival.

Methods:In total, 112 colorectal adenocarcinomas, with a median follow up of 66 months, were studied. The representative tumour sections were stained by the van Gieson method, which stains collagen rich stroma red. For quantitative histochemical measurement, digital images were analysed by a computerised image analysis program to calculate the percentage of red stained tissue area. The percentage of desmoplasia (PD) was related to conventional clinicopathological prognostic factors and overall survival.

Results:The mean (SD) PD was 4.85 (3.37). PD was found to be significantly associated with lymph vessel and venous invasion. By Kaplan–Meier analysis, PD was associated with survival—patients with PD > 4 had a shorter survival than those with PD ⩽ 4. In multivariate analysis, tumour stage, distant metastasis, and PD emerged as independent prognostic factors.

Conclusion:Desmoplasia measured by image analysis seems to be a significant prognostic indicator in patients with colorectal carcinoma and the improved method described in this study would be useful for routine prognostication.
An audit to assess the quality of necropsies performed on stillborn infants
Authors: Burnley H , Moore I
Published: December 2004

Aims:To determine the quality of stillbirth postmortem reports and their contribution to a final diagnosis following the introduction of explicit consent forms after the Alder Hey inquiry.

Methods:Necropsy reports from 100 consecutive stillbirths were reviewed from 2001 onwards. A spreadsheet compiled data items that were considered essential in the Royal College of Pathologists guidelines. The type of consent (with permission for organs/tissue retention) was recorded to assess the impact on establishing a cause of death.

Results:Consent for tissue retention was obtained in 95 cases, whereas consent for organ retention was significantly lower (52 cases). In two cases, permission was refused for tissue retention and three requested external examinations only. Of these five, four had an undetermined cause of death, compared with 35 of 95 cases where permission for tissue retention was granted. All data items considered essential were recorded in every report. In 65 cases, the necropsy provided useful information, helped clinical care, and addressed parental concerns.

Conclusions:There was no major impact of the type of necropsy consent on establishing a cause of death, apart from the case of limited necropsies without histological examination of tissue samples.
INDUCTIVE COMPOSITION OF NUMBERS WITH MAXIMUM, MINIMUM, AND ADDITION: A New Theory for Program Execution-Time Analysis
Authors: WANG FARN
Published: December 2004

We extend the classic work of R.J. Parikh on context-free languages with operators min and max on unary alphabet. The new theory is called CAN (Compositional Algebra of Numbers) and can be used to model software processes that can be concatenated, concurrently executed, and recursively invoked. We propose and analyze an algorithm which constructs the execution time sets of a CAN in semilinear form. Finally, we consider several interesting variations of CAN whose execution time sets can be constructed with algorithms.
OPTIMAL CONTROL OF THE ATMOSPHERIC ARC OF A SPACE SHUTTLE AND NUMERICAL SIMULATIONS WITH MULTIPLE-SHOOTING METHOD
Authors: BONNARD B. , FAUBOURG L. , TRELAT E.
Published: December 2004

This article, continuation of previous works,5,3 presents the applications of geometric optimal control theory to the analysis of the Earth re-entry problem for a space shuttle where the control is the angle of bank, the cost is the total amount of thermal flux, and the system is subject to state constraints on the thermal flux, the normal acceleration and the dynamic pressure. Our analysis is based on the evaluation of the reachable set using the maximum principle and direct computations with the boundary conditions according to the CNES research project. The optimal solution is approximated by a concatenation of bang and boundary arcs, and is numerically computed with a multiple-shooting method.
SEMICLASSICAL STATES FOR COUPLED SCHRÖDINGER–MAXWELL EQUATIONS: CONCENTRATION AROUND A SPHERE
Authors: RUIZ DAVID
Published: December 2004

In this paper we study a coupled nonlinear Schrödinger–Maxwell system of equations. In this framework, we are concerned with the existence of semiclassical states. We use a perturbation scheme in a variational setting in order to study the concentration of the solutions when the Planck constant is supposed to be small enough.
A NOTE ON ADMISSIBLE SOLUTIONS OF 1D SCALAR CONSERVATION LAWS AND 2D HAMILTON–JACOBI EQUATIONS
Authors: AMBROSIO LUIGI , DE LELLIS CAMILLO
Published: December 2004

Let Ω⊂ℝ2be an open set and f∈C2(ℝ) with f" > 0. In this note we prove that entropy solutions of Dtu+Dxf(u) = 0 belong to SBVloc(Ω). As a corollary we prove the same property for gradients of viscosity solutions of planar Hamilton–Jacobi PDEs with uniformly convex Hamiltonians.
HIGH FREQUENCY ANALYSIS OF FAMILIES OF SOLUTIONS TO THE EQUATION OF VISCOELASTICITY OF KELVIN–VOIGT
Authors: ATALLAH-BARAKET AMEL , FERMANIAN KAMMERER CLOTILDE
Published: December 2004

In this paper, we study the evolution of the energy density of a sequence of solutions to the Kelvin–Voigt viscoelasticity equation. We do not suppose lower bounds on the non-negative viscosity matrix. We prove that, in the zone where the viscosity matrix is invertible, this term prevents propagation of concentation and oscillation effects contrary to what happens in the wave equation. We calculate precisely the weak limit of the energy density in terms of microlocal defect measures associated with the initial data under the assumption that the oscillations of the data are not microlocally localized on directions which are in the kernel of the viscosity matrix.
ON A CLASS OF HYPERBOLIC BALANCE LAWS
Authors: COLOMBO RINALDO M. , CORLI ANDREA
Published: December 2004

Consider an n×n system of hyperbolic balance laws with coinciding shock and rarefaction curves. This note proves the well-posedness in the large of this system, provided there exists a domain that is invariant both with respect to the homogeneous conservation law and to the ordinary differential system generated by the right-hand side. No "non-resonance" hypothesis is assumed.
A characterization of the generators of analytic C0‐semigroups in the class of scalar type spectral operators
Authors: Markin Marat V.
Published: December 2004

In the class of scalar type spectral operators in a complex Banach space, a characterization of the generators of analytic C0‐semigroups in terms of the analytic vectors of the operators is found.
The Effect of Detroit’s Living Wage Law on Nonprofit Organizations
Authors: Reynolds David , Vortkamp Jean
Published: December 2004

A common argument made against local passage of living wage laws is that they harm nonprofit organizations by compelling employers—with tight, strained budgets—to increase wages. Ninety-six nonprofits covered by Detroit’s living wage law were contacted 1 1/2 years after the 1998 law had gone into effect. Although a small number of nonprofit employers needed help to implement the living wage requirements, overall, the living wage law neither had a negative effect on nonprofit organizations nor did it result in appreciable job losses. The study’s findings are relevant not simply to other municipalities whose laws cover nonprofit employers but to living wage laws generally. If living wage laws are harmful to employers or employees, the effect should be most pronounced among the most vulnerable employers—namely, nonprofit organizations. This research confirms that living wage requirements do not generally pose a significant cost relative to contract amounts, employers’overall budgets, or the local municipal budget.
LRP2/megalin is required for patterning of the ventral telencephalon
Authors: Spoelgen Robert , Hammes Annette , Anzenberger Uwe , Zechner Dietmar , Andersen Olav M. , Jerchow Boris , Willnow Thomas E.
Published: December 2004

Megalin is a low-density lipoprotein receptor-related protein (LRP2)expressed in the neuroepithelium and the yolk sac of the early embryo. Absence of megalin expression in knockout mice results in holoprosencephaly,indicating an essential yet unidentified function in forebrain development. We used mice with complete or conditional megalin gene inactivation in the embryo to demonstrate that expression of megalin in the neuroepithelium but not in the yolk sac is crucial for brain development. During early forebrain development, megalin deficiency leads to an increase in bone morphogenic protein (Bmp) 4 expression and signaling in the rostral dorsal neuroepithelium, and a subsequent loss of sonic hedgehog (Shh)expression in the ventral forebrain. As a consequence of absent SHH activity,ventrally derived oligodendroglial and interneuronal cell populations are lost in the forebrain of megalin–/– embryos. Similar defects are seen in models with enhanced signaling through BMPs, central regulators of neural tube patterning. Because megalin mediates endocytic uptake and degradation of BMP4, these findings indicate a role for megalin in neural tube specification, possibly by acting as BMP4 clearance receptor in the neuroepithelium.
Survival and Growth of Lake Whitefish from Two Stocking Strategies in Lake Simcoe, Ontario
Authors: Amtstaetter Frank , Willox Campbell C.
Published: December 2004

To determine the more efficient stocking strategy for lake whitefish Coregonus clupeaformis in Lake Simcoe, Ontario, we compared growth and survival of fish stocked as fall fingerlings and as spring yearlings. Paired lots were stocked in April and October from the 1986 to 1991 year-classes. Survival and growth of fish from the two rearing practices were indexed as the relative abundance and length of 6-year-old lake whitefish captured with trap nets during fall spawning runs from 1992 to 1997. No difference in relative abundance or length between lake whitefish stocked at 6 months of age and those stocked at 12 months of age was detected. This contradicts results reported for many other fish species, which have exhibited greater survival rates when stocked as yearlings rather than fingerlings. As a result of these findings, all lake whitefish stocked into Lake Simcoe are stocked in the fall when the fish are 6 months of age, thus freeing up limited hatchery space for other purposes.
Effectiveness of High-Velocity Inclined Profile-Bar Fish Screens Measured by Exclusion and Survival of Early Life Stages of Fathead Minnow
Authors: Bestgen Kevin R. , Bundy Jay M. , Zelasko Koreen A. , Wahl Tony L.
Published: December 2004

We estimated exclusion and survival rates of fathead minnow Pimephales promelas exposed to four configurations of a high-velocity inclined profile-bar screen. These screens are functionally different from conventional positive-barrier designs because fish behavior and swimming ability are not design considerations. We tested screens inclined at 45° or 60° that had 1.0-mm or 0.5-mm slot widths and used 5–45-mm total length fathead minnow released high or low in the water column. The exclusion rate for 45.0-mm and 22.5-mm fathead minnow was 100%. Survival of 45.0-mm fish was 88%; latent mortalities were attributable to nonscreen causes. Survival of 22.5-mm fish was 100%. Exclusion rates for high- and low-release 12.5-mm fathead minnow were nearly 100%. Survival rates for high-release 12.5-mm fathead minnow were 62– 86% and were similar to or higher than those for low-release fish (15–71%). Exclusion rates of 7.5-mm and 5.0-mm fathead minnow in tests with the 0.5-mm screen were 88–95% regardless of release position. Exclusion rates for 7.5-mm and 5.0-mm fish tested with 1.0-mm screens were mostly lower (2–90%), especially for low-release fish. Survival rates for 7.5-mm fathead minnow in high releases were 26–62%, but survival rates for low-release 7.5-mm fish (0–9%) and 5.0-mm fish (28%) were low. The screen angles we tested had little consistent effect on exclusion or survival rates. The successful exclusion and survival we documented for various life history stages of fathead minnow, coupled with the high hydraulic efficiency and self-cleaning properties of high-velocity inclined profile-bar fish screens, indicates that this is a potentially effective tool for managers seeking to reduce entrainment loss of fish in aquatic ecosystems.
Temporal and Spatial Estimates of Adult Striped Bass Mortality from Telemetry and Transmitter Return Data
Authors: Young Shawn P. , Isely J. Jeffery
Published: December 2004

Estimates of total mortality, fishing mortality, and natural mortality in the fishery for the adult striped bass Morone saxatilis in J. Strom Thurmond Reservoir, South Carolina–Georgia, were determined from long-term radiotelemetry data and high-reward radio transmitter return data using catch curve analyses. Annual total mortality rates were 0.81 ± 0.06 (mean ± SE) for year 1 (July 1999–June 2000) and 0.42 ± 0.04 for year 2 (July 2000–June 2001). We observed that the force of fishing was much greater than the force of natural death on total mortality in this fishery. Total exploitation of all implanted striped bass over the 2-year study period was 48%. Fishing mortality rates were 0.67 ± 0.04 for year 1 and 0.33 ± 0.02 for year 2, and natural mortality rates were 0.14 ± 0.02 for year 1 and 0.09 ± 0.02 for year 2. We also identified seasonal increases in total and fishing mortality rates from July to September. Fishing mortality was highest temporally and spatially during late spring and late summer near the tailrace below Richard B. Russell Dam owing to high angling pressure for striped bass while the fish were congregated in summer refugia. Natural mortality occurred only during mid to late summer in the middle section of the reservoir. These deaths were attributed to striped bass's becoming trapped in unsuitable summer habitat in the lower and middle sections of the reservoir. Mean postsurgery growth from 15 harvested study fish at large for a mean of 1.16 ± 0.81 years was estimated to be 1.71 ± 0.73 kg/year. Internal implantation of telemetry devices appeared to have no negative effect on long-term growth, health, and survival of adult striped bass and did not bias mortality and survival estimates.
Seasonal Movement of Brown Trout in the Clinch River, Tennessee
Authors: Bettinger Jason M. , Bettoli Phillip W.
Published: December 2004

We used radiotelemetry to monitor the seasonal movements of trophy-size brown trout Salmo trutta in the Clinch River below Norris Dam, Tennessee, to determine whether establishing a special-regulation reach to reduce fishing mortality was a viable management option. Fifteen brown trout (size range, 430–573 mm total length) collected from the river were implanted with radio transmitters between November 1997 and May 1998. Forty-seven percent of these fish died or expelled their transmitters within 50 d postsurgery. The range of movement for surviving brown trout was significantly larger in fall (geometric mean range = 5,111 m) than in any other season. Four brown trout that were monitored for more than 1 year exhibited a limited range of movement (<2 km) during the winter, spring, and summer, but they made extensive movements (>5 km) during the fall season, presumably to spawn. Brown trout also moved more during the fall than in any other season. Harvest restrictions applied to a specific reach of the Clinch River would reduce the exploitation of brown trout in that reach for most of the year but not during the fall, when many fish undertake extensive spawning migrations.
Effects of Absorbable Suture Strand Diameter on Retention of External Radio Transmitters by Juvenile Lake Sturgeon
Authors: Sutton Trent M. , Volkman Eric T. , Pangle Kevin L. , Rajchel Deborah A. , Duehr Jeremy P.
Published: December 2004

We evaluated the effects of four absorbable suture strand diameters (numbers 3/0, 0, 1, and 2 [from smallest to largest diameter]) on the short-term retention of externally attached dummy radio transmitters by juvenile lake sturgeon Acipenser fulvescens (fork-length range, 257–293 mm; wet-weight range, 100–132 g). Four lake sturgeon were contained in each of 10 aquaria, and one fish in each tank was assigned to each of the four suture treatment groups. Transmitter retention was positively related to suture strand diameter, the mean retention duration for number 2 sutures being nearly twice as long (21 d) as that of number 3/0 sutures (11.8 d). The smallest suture (number 3/0) also exhibited the fewest number of days to transmitter loss (25% loss, 9 d; 50% loss, 11 d; and 75% loss, 14 d). In contrast, the largest suture (number 2) had the greatest number of days to transmitter loss (25% loss, 16 d; 50% loss, 21 d; and 75% loss, 26 d). Based on the diameter of sutures examined in this study, we recommend number 2 absorbable sutures for externally affixing radio transmitters to ensure adequate retention of short-term tags using this novel attachment approach for telemetry studies involving juvenile lake sturgeon.
Abundance and Size Distribution of Ocean-Type Juvenile Chinook Salmon in the Upper Sacramento River Margin before and after Hatchery Releases
Authors: Weber Edward D. , Fausch Kurt D.
Published: December 2004

If hatchery-reared salmon delay emigration after release, they may compete with wild salmon in freshwater rearing habitat. We measured the densities and size distributions of ocean-type juvenile Chinook salmon Oncorhynchus tshawytscha in two rearing areas downstream of a hatchery in the Sacramento River, California, before, during, and after two large releases in both 2001 and 2002. Densities of juvenile salmon followed a unimodal trend through time, peaking at about 0.5–1.5 fish/m2 during late March or early April but declining by the time hatchery fish were released in mid to late April. Hatchery releases did not increase densities above the underlying trend, except after one release at one site. Density increased by 0.83 fish/m2 (SE, 0.30 fish/m2) after this release but returned to the baseline level within 3 d. Although hatchery fish were much larger than most wild fish, the mean size of fish captured did not increase appreciably after hatchery releases, even after the release when density increased. These data suggest that the strategy of delaying hatchery releases until many hatchery fish were smoltifying and many wild fish have emigrated was relatively effective in reducing potential interactions in freshwater rearing areas of the stream margin in the upper river.
Methods for Predicting Age-0 Crappie Year-Class Strength in J. Percy Priest Reservoir, Tennessee
Authors: St. John R. Todd , Black William Patrick
Published: December 2004

We evaluated the precision and efficiency of larval townets and trap nets and correlated estimates to hydrologic parameters (temperature and spring discharge) during 1998–2002 to determine the best method for predicting year-class strength of age-0 white crappie Pomoxis annularis and black crappie P. nigromaculatus in J. Percy Priest Reservoir, Tennessee. Both larval townet and fall trap-net samples effectively sampled age-0 Pomoxis spp. and accurately indexed year-class strength. The geometric mean density of larval Pomoxis spp. in townet samples for the 3-week period bracketing peak density provided a more precise estimate of larval crappie density than the geometric mean of the 1-week peak. Larval density in May was correlated to age-0 catches in fall trap nets, so density of larval Pomoxis spp. was positively related to year-class strength. However, fall trap-net samples of age-0 Pomoxis spp. provided a more precise and cost-effective index of year-class strength than larval townet samples. May discharge through the dam was an accurate predictor of age-0 abundance in fall trap nets. This negative relation provides an early prediction of year-class strength and will be useful for supplemental stocking strategies and harvest regulation proposals.
Dichroic dyes, and liquid crystalline side chain polymers
Authors: Schinidt Hans‐Werner
Published: December 2004

Functional guest molecules incorporated into LC‐side‐chain polymers lead to polymeric materials which combine the physical and optical anisotropic properties of liquid crystals with the special functions of the guest components. This contribution focused on dichroic dyes, but the results are transferable to other guest moieties. The covalent fixation of the dye to the polymer backbone affords several advantages. Liquid crystalline materials with high dye concentrations were obtained opening the way to the preparation of highly ordered, optical uniaxial films with adjustable thickness and optical density. Thin well aligned LC‐polymer films can in principle be used as an active medium for reversible optical information storage and mixtures of dye‐containing copolymers in low molar mass liquid crystals can be used in displays. Current developments in the area of ferroelectric chiral smectic‐C side‐chain polymers will further enhance interest in this area.
Production and application of Rapidly Quenched Materials
Authors: Warlimont Hans
Published: December 2004

Amorphous metals produced by rapid quenching from the melt can be formed into ribbons (see figure) and can be greatly useful for speciality magnetic applications. In transformers, for example, power loss is greatly reduced when amorphous core transformers are used. This short review gives a taste of what can be achieved using Rapid Solidification Technology.

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Materials for biomedical application– high long‐term success rates might pose new problems
Authors: Heimke Ganther
Published: December 2004

The increasing functional lifetime of modern implants has been due to engineering successes in utilizing new materials. However, along with this progress has come the concern that some of these materials are not as biologically inert as expected and systemic damage may in some cases be caused. Second article in a quarterly series.

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Structure‐Directed Synthesis of new organic materials
Authors: Kohnke Franz H. , Mathias John P. , Stoddart J. Fraser
Published: December 2004

The synthesis of molecular cages, belts and strips opens up new areas of technology for exploitation. Solvent specific sensors are one possible use of cage molecules called carcerands (see figure). A series of Diels Alder reactions under tight stereochemical control are used in a remarkably efficient manner to produce the structures.

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Siloxane copolymers with laterally and terminally attached mesogenic side chains
Authors: Gray G. W. , Hill J. S. , Lacey D.
Published: December 2004

Liquid crystals based on polysiloxane copolymers (see figure) with well defined physical characteristics have been synthesized by varying the type and ratio of the laterally attached mesogenic side chains. Applications in integrated optics and optical storage are envisaged.

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Phase equilibria under stress
Authors: Cahn Robert W.
Published: December 2004

A slight mismatch between the lattice parameters of two intergrown “coherent” phases can cause internal stresses within a two phase alloy which can modify the shapes of the dispersed phase particles. Recent studies by both metallurgists and geologists have been aimed at understanding this and other stress related phenomena.
A semiconductive nickel‐‐phosphine coordination polymer**
Authors: Fox Marye Anne , Chandler Daniel A.
Published: December 2004

Communication: Organometallic polymers with a transition‐metal ion incorporated into a conjugated chain are of potential interest as conductors and semiconductors. The structural criteria which are known to enhance conductivity, such as strong ligand–metal interactions, co‐planarity of aromatic ligands, and high molecular weight, are met by the new material shown in the Figure.

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The methylation of arsenic in marine sediments
Authors: Reimer Kenneth J
Published: December 2004

Laboratory studies have shown that microorganisms present in both natural marine sediments and sediments contaminated with mine‐tailings are capable of methylating arsenic under aerobic and anaerobic conditions.

Incubation of sediments with culture media produced volatile arsines [including AsH3, (CH3)AsH2, and (CH3)3As] as well as the methylarsenic(V) compounds (CH3)nAs(O) (OH)3−n (n = 1, 2, 3). The concentration of the arsines increased and then decreased in a growth and decay pattern reminiscent of the methylation and demethylation of mercury. Thus, arsenic speciation varied with time, being controlled by the biochemical activity of the dominant microbe(s) at the time of sampling, and changing in response to the ecological succession within the microbial community.

The analysis of the interstitial waters of sediments collected from several British Columbia (Canada) coastal sites gave results that were consistent with the culture experiments, in that the methylarsenicals were ubiquitous, but present only in small amounts. It is estimated that methylarsenic(V) species account for less than 1% of the arsenic present in porewaters. The actual proportion was dependent on a number of factors but, contrary to prevailing viewpoints, there was no relationship to the organic content of the sediments, nor did methylation occur only in the presence of high arsenic concentrations. Instead, all of the evidence was consistent with in situ microbial methylation and demethylation processes that are similar to the arsenic transformations that occur in soil ecosystems.

The results are discussed in terms of the cycling of arsenic in the marine environment and within the marine food web.
Assessment of the in vitro broad‐spectrum antiviral activity of some selected antitumor metallocene and metallocenium complexes
Authors: Ward Sarah G , Taylor R Craig , Köpf‐Maier Petra , Köpf Hartmut , Balzarini Jan , De Clercq Erik
Published: December 2004

Six neutral metallocenes and six metallocenium salts, all of which have demonstrated antiproliferative properties, were evaluated for their in vitro broad‐spectrum antiviral properties and cytotoxicities. The metallocenes include the compounds (η‐C5H5)2MCl2, Where MTi, V, Mo, Zr and Hf, and (η‐C5H5)2Tibis(hydrogen maleinate), whereas the metallocenium complexes include the three ferrocenium salts, (η‐C5H5)2Fe+X−, where X− = trichloroacetate, tetrachloroferrate(III) and picrate, and three recently discovered antitumor titanocenium complexes, i.e. [(η‐C5H5)2Ti(CH3CN)Cl+] [FeCl], [(η‐C5H5)2Ti(2,2′‐bipyridyl)2+][CF3SO]2, and [(η‐C5H5)2Ti(N‐methyl‐o‐aminothiophenolate+)] [I−]. These 12 species were evaluated against DNA viruses (herpes simplex virus type 1, type 2 and vaccinia virus), and RNA viruses [vesicular stomatitis virus, Coxsackie virus B4, Sindbis virus, Semliki forest virus, parainfluenza virus type 3 and human immunodeficiency virus type 1 (HIV‐1), the etiologic agent of AIDS]. In the case of HIV‐1, the complexes were evaluated for their ability to inhibit HIV‐associated reverse transcriptase activity and HIV‐1 induced cytopathogenicity in human T‐lymphocyte MT4 cells. Selectivity indexes [ratio of the minimum cytotoxic concentration (does) to the minimum (antiviral) inhibitory concentration (dose)] were determined for all complexes and viruses. In general, the netural metallocenes and the ferrocenium salts were only marginally active towards some specific viruses. However,[(η‐C5H5)2Ti(bipy)] [CF3SO]2 was active towards the DNA viruses at a concentration that was ten times lower than the cytotoxicity threshold. (η‐C5H5)2VCL2 was weakly inhibitory towards HIV reverse transcriptase. All species were ineffective in inhibiting HIV‐induced cytopathogenicity in human T‐lymphocyte MT4 cells.
Structural effects on the antitumour activity of a series of di(4‐substituted phenyl)tin dichloride complexes with nitrogen‐donor ligands
Authors: Biddle Brain N , Gray John S
Published: December 2004

Investigation of the antitumour activity of a series of diorganotin dichloride complexes (4‐ZC6H4)2SnCl2·L2, where Z = OMe, Me, F, Cl, and CF3 and L2 = 2,2′‐bipyridyl (bipy), 1,10‐phenanthroline (phen) and 2‐aminomethylpyridine (amp) is reported. A number of these complexex are shown to exhibit reproducible activity in vivo towards P388 lymphocytic leukaemia in mice. 1H NMR data are reported for an extended series of (4‐ZC6H4)4Sn and the parent dichlorides (4‐ZC6H4)2SnCl2 of the above‐mentioned complexes. A correlation is reported between Hammett substituent constants and 1H chemical shift data. Attempts are made to relate the antitumour activity of the complexes to various structural factors. The dependence of antitumour activity on the electronic effect of group Z and the nature of the ligand L2 is demonstrated.
Photochemistry of iron pentacarbonyl in poly(vinyl chloride), polytetrafluoroethylene and low‐density polyethylene films at 12–298 K: Infrared spectroscopic evidence for the reversible formation of the carbon monoxide loss products iron tetracarbonyl and tricarbonyl, and their reactions with species in the films
Authors: Hooker Richard H , Rest Antony J
Published: December 2004

Infrared spectroscopic evidence (CO stretching region) is presented to show that near‐UV irradiation (280 < λ < 350 nm) of Fe(CO)5 in lowdensity polyethylene (LDPE), poly(vinyl chloride) (PVC) and polytetrafluoroethylene (PTFE) films at ca 12 K affords the coordimatively unsturated species Fe(CO)4 and Fe(CO)3. The species Fe(CO)3 recombines with CO at ca 60 K whilst Fe(CO)4 recombines at ca 80 K. The species also react with the polymeric medium and with residual solvent molecules [hexane, dichloroethane, tetrahydrofuran (THF)] in the films. The species Fe(CO)4…(PVC) and Fe(CO)4…(dichloroethane), in which the Fe(CO)4 fragments are probably coordinated by chlorine atoms in the PVC or solvent molecules, are less thermally stable than Fe(CO)4(THF) and are converted to Fe(CO)5 on warming the films to above ca 140 K. Similarly, the species Fe(CO)4(LDPE) and Fe(CO)4(hexane), arising from interaction of Fe(CO)4 with hydrogen atoms in the polymer or solvent molecules, are converted to Fe(CO)5 on warming the films from ca 100 K to ca 130 K. The major product formed in LDPE films at 298 K is probably Fe(CO)4(olefin) arising from olefin impurities in the poly(ethylene), whilst in the PVC films in the presence or absence of THF the major product resembles (η3–C3H5)Fe(CO)3Cl, i.e. Fe(CO)4 and Fe(CO)3 fragments bound to allyl chloride impurities in the PVC. The potential of polymer films for trapping and characterizing unstable species is discussed.
Organopolysilanes as photopolymerization initiators of polymethylvinylsiloxanes and polydimethylsiloxanes
Authors: Semenov V V , Cherepennikova N F , Artemicheva S B , Razuvaev G A
Published: December 2004

The organopolysilanes Me(Me2Si)nMe (n = 4–6), (Me2Si)6 and (Me3Si)2SiMePh are found to be effective photoinitiators for the polymerization of vinyl‐containing siloxane rubbers. The trisilanes Me(ME2Si)3Me and Me3SiSiMe2SiMe2Ph are slightly effective, while phenyldisilanes do not exhibit initiation activity in the process of photocuring. Polydimethylsiloxanes are cured at a slower rate under the same conditions than vinylcontaining derivatives. Two mechanisms of crosslinking are proposed: silylene–silirane–silanol and silylene–hydride–silanol.
A thermal analytical study of some mono‐ and di‐organotin oxides and carboxylates
Authors: Blunden S J , Hill R , Sutton S E
Published: December 2004

Simultaneous thermogravimetry and differential thermal analysis studies on a variety of mono‐ and di‐organotin oxides and carboxylates were performed; for the carboxylates, these studies followed 119Sn NMR spectroscopic investigation. All the organotin compounds thermally degrade to tin (;IV) oxide (;SnO2) in either air or oxygen, as was confirmed by Mössbauer spectroscopy in the cases of RSn(;O)OH (;R=butyl, octyl) and Bu2SnO.

The organotins are less stable than previously believed since evidence for degradation was obtained in many cases at approximately 160–170 °C.

In addition it was found that oxygen influences the thermal stability of the organotins, since Bu2SnO did not degrade when heated for 1 h at 280 °C under nitrogen, yet readily broke down at 170 °C in air. Furthermore, pure oxygen had the effect of lowering reaction temperatures by approximately 10–12°C compared with those in air.
Highly efficient formation of metal and metal alloy particles from methyl metal compounds by a single pulse laser irradiation
Authors: Shimo Nobuo , Fujita Masato , Kuma Hitoshi
Published: December 2004

Highly efficient processes for fine particle formation of metal alloys and metal oxides were developed using a high‐power laser. In these processes, laser light was used only for the ignition of a thermal chain reaction. This reaction was suppressed by adding inert gases, and the suppression effect was in the order C3H8 > C2H6 > CH4 > He > Ar > Xe. Oxygen accelerated the reaction because of the large exothermicity of the reaction of oxygen with methyl metal compounds.
Functionalization and further crosslinking of the nicalon polycarbosilane based on its metalation with the n‐butyllithium—postassium t‐butoxide reagent
Authors: Seyferth Dietmar , Lang Heinrich
Published: December 2004

Reaction of the Nicalon polycarbosilane with the n‐BuLi/Me3COK reagent resulted in metalation of approximately one CH2 group in four. Reaction of the metalated polymer with Me2 (CH2 = CH)SiCl gave a Me2(CH2 = CH)Si‐substitued Nicalon polycarbosilane. The polymer was heated with different amounts of the [(MeSiH)∼0.8(MeSi)∼0.2]n polysilane in the presence of azobisisobutyronitrile in refluxing benezene. Hydrosilylation by the SiH‐containing polysilane of the CH2CH groups of the Me2(CH2CH) Si‐substituted Nicalon polycarbosilane gave a new hybrid polymer (when appropriate quantities of reactant polymers were used) whose pyrolyis in a stream of argon to 1000°C left a ceramic residue in 77% yield whose elemental analysis indicated a nominal composition of 91% by weight SiC and 9% C.
Formation of arynezirconocenes from substituted diaryl bis (t‐butylcyclopentadienyl) zirconium: application to the synthesis of new functionalized ortho‐dichalcogenobenzene compounds
Authors: Bodiguel J , Meunier P , Gautheron B
Published: December 2004

The para‐substituted diphenylzirconocenes [(t‐BuCp)2Zr(p‐C6H4R)2; R = Br, NMe2] (A) were easily obtained from the reaction of the appropriate organolithium reagent with bis(t‐butylcyclopentadienyl)zirconium dichloride. Elimination of bromobenzene or N,N‐dimethylaminobenzene from A by slight heating led to arynezirconocenes into which were inserted two equivalents of elementary chalcogens. As a result dichalcogenated zirconacycles [(t‐BuCp)2ZrY2C6H3R; Y = S, Se] (B) were obtained. Complexes B constitute useful potential synthons in organic synthesis and a large family of new functionalized dichalcogenated benzenic compounds was prepared by reacting electrophiles.

The structure of complexes B as well as related benzenic derivatives has been confirmed by microanalysis, 1H NMR and mass spectrometry.
Identification of microglia in light and electron microscopy
Authors: Mori Shiro , Leblond C. P.
Published: December 2004

The corpus callosum of 60–80 gm male rats was processed by the weak silver carbonate method of del Rio‐Hortega for the detection of microglia in the light microscope. Because of the opacity of the metal stain taken up by these cells, they could be recognized in the electron microscope. The characteristic features of microglia were thus found to be a small nucleus in which dark chromatin contrasts with light nucleoplasm, and a cytoplasm containing dense bodies (presumed to be lysosomes) and poor in endoplasmic reticulum. After gaining experience with microglia in the electron microscope, it became possible to recognize their features in 0.5–1 μ thick toluidine blue stained Epon sections examined in the light microscope.

In the electron microscope, some microglia are found within expansions of the basement membrane of capillaries (pericytal microglia); they usually have little cytoplasm, few dense bodies and few processes. There is evidence that these cells can break out of their basement membrane enclosure and enter the brain tissue proper. There, they scatter singly between other cells and fibers. These cells (interstitial microglia) send of long processes. They may contain numerous dense bodies and be surrounded by irregular spaces (suggesting the existence of surface activity). These observations support the classical view of microglia as brain macrophages.

Microglia constitute 5.5% of the glial population of the corpus callosum. After injection of 3H‐thymidine and radioautography in the light or electron microscope, none showed labeling. Hence, it is presumed that microglia do not proliferate under normal conditions.
Cell changes in sensory ganglia following proximal and disal nerve section in the monkey
Authors: Carmel Peter W. , Stein Bennett M.
Published: December 2004

Ganglion cell changes were studied in 25 monkeys following systematic section of spinal and cranial sensory nerves proximal or distal to the ganglion. Ganglion cells were studied in Nissl preparations while central degeneration was studied in Nauta‐Gygax stained sections. Morphological characteristics of normal ganglia were studied in unoperated controls.

In normal ganglia three categories of cells were identified: (1) A predominant largecelled group (ranging from 20 to 100 μ), (2) small dark cells, and (3) a small number of “atypical” cells.

Division of nerves proximal to ganglia produced no cellular changes in most cases; changes attributed to relative ischemia occurred in a few ganglia. Centrally projecting fibers of sectioned nerves were degenerated.

Division of sensory nerves distal to ganglia produced profuse chromatolytic changes in cells of all sizes and types within ganglia but no central degeneration. Cervical section of the vagus produced chromatolytic cell changes in the inferior ganglion and a small portion of the superior ganglion unrelated to the auricular nerve. Section of the facial nerve distal to the geniculate ganglion produced chromatolysis in approximately half of the ganglion cells. An accessory trigeminal ganglion, composed of cells of autonomic type, was found distal to the trigeminal ganglion in association with the third division of the nerve.

Severance of nerve fibers distal to sensory ganglia eliminates peripheral neurotrophic influences necessary for the growth and maintenance of the ganglion cell. It is postulated that the integrity of this influence is sufficient to sustain sensory ganglion cells after their central processes have been sectioned.
The fine morphology of the sensory receptor organs in the auricle of the rat
Authors: Cauna Nikolajs
Published: December 2004

The fine structure, distribution of cholinesterase activity and microtopography of the sensory receptor organs of the rat's auricle were studied in six animals. It was found that the skin of the auricle consisted of minute but well defined receptor territories each supplied by a morphologically distinct nerve ending.

The horizontal endings, derived from non‐myelinated nerve fibers, supplied linear skin areas covering the intervals between the hair orifices and sending fine twigs into the epidermis. They had the simplest morphology and showed no cholinesterase activity.

The papillary endings were restricted to the immediate vicinity of the hair orifices. They exhibited butyrocholinesterase activity and showed a typical fine morphology. The expanded axon terminals were filled with mitochondria and enclosed by Schwann cells of some complexity.

The nerve endings of the fine hairs were derived from myelinated axons. The endings showed acetyl‐ and butyrocholinesterase activity. The terminal fibers ended in spindles that were arranged longitudinally in a semicircle around the epithelial root sheath of the hair forming a single layer between the orifices of the sebaceous glands and the base of the hair follicle. The endings were characterized by the accumulation of mitochondria and microvesicles in the terminal spindles and by the high pinocytotic activity in the associated Schwann cell processes.

The deep tissues contained at least one kind of simple beaded nerve ending that gave a negative cholinesterase reaction.

It was concluded that the morphological diversity of the sensory apparatus was adequate to account for a considerable degree of specificity or at least selectivity of its end organs.
The primary optic projections in the rabbit. An experimental degeneration study
Authors: Giolli Roland A. , Guthrie Mary D.
Published: December 2004

The brains of ten rabbits (4 pigmented and 6 albino) sacrificed 6–21 days after unilateral ocular enucleation were prepared by Nauta and Nissl methods and used to study the projection and terminal destribution of degenerating optic axons. The retina is bilaterally represented in the alpha sectors of both ventral and dorsal lateral geniculate nuclei (LGv and LGd), in n. tractus opticus (NTO), in the dorsolateral portions of nn. praetectalis anterior (NPA) and posterior (NPP), and in the superior colliculus (SC). The retina is unilaterally represented in the contralateral terminal accessory optic nuclei.

The mode of termination of crossed and uncrossed retinal projections endows the LGd with a concealed laminar organization. Four laminae are recognized and numbered consecutively from lateral to medial. Lamina one is extensive and formed entirely of crossed retinal input. The remaining three laminae occupy the medial zone of the LGd. Of these, laminae two and four are innervated predommantly by the ipsilateral retina while lamina three is supplied mainly by the contralateral retina. Uncrossed retinal innervations of LGv, NTO, NPA, NPP and SC are scant and overlapped entirely by crossed retinal inputs. Chiasmal decussation of the optic nerve is 90–95% complete with the uncrossed component, and specifically the uncrossed retino‐LGd and ‐SC projections, being larger in pigmented as compared with albino rabbits.
Monoamine‐containing neurons in the central nervous system and peripheral nerves of the leech, Hirudo medicinalis
Authors: Rude Sonia
Published: December 2004

The 34 ganglia of the leech (Hirudo medicinalis) central nervous system together with their connectives and roots have been studied by means of the fluorescence histochemical technique for monoamines.

More than half the ganglia of the central nervous system possess the same number of monoamine‐containing neurons in a fixed location. These identical ganglia consist of seven yellow fluorescent monoamine‐containing neuron perikarya located within the ganglia and a pair of blue‐green fluorescent monoamine‐containing perikarya located outside the ganglia in the anterior roots. A neuropile consisting of a dense network of yellow and blue‐green fluorescent varicose processes, several smooth blue‐green fluorescent processes and occasional smooth yellow fluorescent processes is present in the ganglia. Smooth and varicose yellow and blue‐green fluorescent processes are found in the connectives and roots of the ganglia. The intraneuronal distribution of fluorescence within the nine monoamine‐containing neurons of identical ganglia is described.

The monoamine‐containing neurons of the remaining ganglia of the central nervous system are described. These ganglia are shown to vary only slightly from the pattern of identical ganglia.
Identification of beta fibers at spindle entry
Authors: Berndt J. M. , Oswaldo‐Cruz E. , Rocha‐Miranda C. E.
Published: December 2004

Using a silver impregnation technique, mainly in teased material, the pattern of muscle spindle motor innervation was compared between reptilian and marsupial material. It was concluded that, although rare, beta fibers (motor nerve fibers which innervate intra‐ and extrafusal muscle fibers) can also be detected at spindle entry in reptiles and in mammals, but that the occurrence is higher in reptilian material.
Cytoarchitecture of the cochlear nuclei in the cat
Authors: Osen Kirsten Kjelsberg
Published: December 2004

The microscopical structure of the cat cochlear nuclei was studied in Nissl preparations in order to get a suitable map for further experimental investigations. The neurons of the entire nuclear complex were classified into nine different types according to their microscopical appearance. Seven of the nine types, viz., the large spherical cells, small spherical cells, octopus cells, globular cells, pyramidal cells, giant cells, and granular cells, seem to constitute rather uniform cell groups, while the remaining types, viz., the multipolar cells and small cells, seem to be rather heteromorphic. On the basis of the distribution of these cell types the nuclear complex was divided into a corresponding number of cell areas which proved to be partly overlapping. This principle of parcellation led to a certain simplification of the previously proposed schemes of the organization of the cochlear nuclei based on cellular characteristics.
Efferent projections of the anterior olfactory nucleus
Authors: Ferrer Nathaniel G.
Published: December 2004

The efferent projection fibers from the rostral and the medial segments of the anterior olfactory nucleus have been studied using the Nauta or the Fink modification of the Nauta method for degenrating axons. Lesions were suitably placed by electrocoagulation. From the rostral segment of the anterior olfactory nucleus efferent fibers by way of the bulbar part of the anterior commissure were traced to the internal granular and the mitral cell layer of the normal side. Preterminal and terminal degeneration were traced by way of the homolateral lateral olfactory tract and these fibers ended in the lateral two‐thirds of the olfactory tubercle, the prepiriform, the piriform and the periamygdalar cortices and into the corticomedial segment of the amygdaloid complex. Degenerating fibers were also noted in the dorsomedial nucleus, the lateral habenular nucleus, the lateral hypothalamic area and in the supraoptic area of the same side where the lesion was made. In animals where the lesion was placed in the medial segment of the anterior olfactory nucleus the same fiber distribution was observed as reported when the lesion was placed in the rostral segment of the anterior olfactory nucleus. However, other areas were observed receiving fibers from the medial segment of the nucleus. These areas were the basolateral segment of the amygdaloid complex and the mammillary areas.