bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Barrier Cabinet for Mice Based on the Houghton Chicken Isolator
Authors: Skinner H. H. , Knight E. H. , Moore D. R. 
Published: June 2007

Summary Nuclei of a disease-free foundation stock of mice housed in a barrier unit and a barrier cabinet constructed from resin-bonded glass-fibre were compared over a period of 7 years. The cabinet was found to be a satisfactory alternative to a flexible-film isolator and was thought to be preferable. A description is given of the cabinet, the method of sterilization and the breeding schedules for 2 generations adopted to make the maximum use of the 10–month life of the high-efficiency filter employed. Throughout many cycles of this duration the degree of cleanliness was of a high order. A major contribution towards this was the collection of excreta on a tray lined with both absorbent and grease-proof paper, and the removal from the cabinet of dirty boxes when weaners were issued in them at the age of 5 weeks. These boxes were replaced in the cabinet by clean, sterile ones.
Breeding Performance of a Captive Colony of Rhesus Macaques (Macaca Mulatto)
Authors: Anderson Donna Marie , Simpson M. J. A. 
Published: June 2007

Summary For most of the 18 years recorded, fewer than 50% of the adult females gave birth in any one year. The colony, of 6 social groups, showed a clear-cut breeding season. Female parity and dominance had no effect on breeding rate, though 1st infants were born earlier in the year than 2nd-born ones. Only when females gave birth in successive years were the months of giving birth correlated. Mothers and daughters may tend to give birth closer in time within a breeding season than do other females.
Warfarin-Resistance Genotype Determination in the Norway Rat, Rattus Norvegicus
Authors: Martin A. D. , Steed Linda C. , Redfern R. , Gill J. E. , Huson L. W. 
Published: June 2007

Summary The 2-stage determination is based on changes in blood coagulation activity brought about both by the administration of warfarin in conjunction with vitamin K1 epoxide and by feeding a vitamin K-free diet for 4 days. When it was applied to laboratory-bred rats of known warfarin-resistance genotype, 35/35 homozygous susceptible, 44/44 homozygous resistant and 131/133 heterozygous rats were correctly classified. This method was equally effective in identifying the genotype of wild rats carrying the warfarin-resistance gene, Rw2. The procedure is rapid and accurate.
Naturally-Occurring Neoplasms in the Mongolian Gerbil, Meriones Unguiculatus
Authors: Meckley Paul E. , Zwicker Gary M. 
Published: June 2007

Summary 10 spontaneous tumours were observed. Several had not been previously reported for this species and 1 occurred in the youngest gerbil yet reported to have a spontaneous tumour. 7 of the 10 tumours originated from the female reproductive tract.
Electrocardiogram of the reindeer, Rangifer tarandus tarandus
Authors: TimisjÄrvi J. , Hirvonen L. , JÄrvensivu P. , Nieminen M. 
Published: June 2007

Summary Electrocardiograms were recorded for 50 Finnish reindeer of age 1 day to 9 years, using standard and unipolar extremity leads in the frontal plane. The range of heart rate was 40–250 beats per minute. Atrial and ventricular depolarization times were 5–10 ms shorter in newborn calves than in older reindeer, and showed only minor variance with respect to heart rate. The duration of depolarization was dependant on heart rate, and was more rapid in young calves. A-V conduction time decreased with increasing heart rate. The mode of the QRS vector was 280–290°, and the mode of the T vector 200–230° in the older animals, but 100–120° in young calves. The main deflection in the QRS complex was S in the leads II, III and aVF. R was dominant in aVL and I.
Dietary habits relating to 'wasting marmoset syndrome' (WMS)
Authors: Shimwell M. , Warrington B. F. , Fowler J. S. L. 
Published: June 2007

Summary The syndrome is a condition of poor weight gain and weakness. Changed eating habits of animals suffering from it lead to consumption of a poorly-balanced diet. By softening the diet and avoiding less nutritious foods, the eating habits can be improved and the syndrome halted. Particular attention should be paid to the palatibility of high-protein foods when weaning marmosets.
Fractional extracellular space and fractional water content of various rat tissues at different extracellular pH values and in uremia
Authors: Rothe K. F. 
Published: June 2007

Summary At different extracellular pH values fractional extra-cellular space (calculated from the distribution of 3H inulin) and fractional water content showed no significant differences. 72 h after nephrectomy both variables increased significantly. An exception to this was brain, where fractional extracellular space decreased and total intracellular water increased as a sign of brain oedema.
Transfer isolator to protect personnel from exposure to peracetic acid
Authors: Trexler P. C. 
Published: June 2007

Summary A transfer isolator is described which confines peracetic acid fumes used in the gnotobiotic operation of isolators. The use of this isolator protects both personnel and animals from contact with peracetic acid, provides additional isolator space and reduces wear on the gloves and sleeves of the main isolator.
Vaginal Opening in the Mongolian Gerbil, Meriones Unguiculatus: Normal Data and the Influence of Social Factors
Authors: Norris M. L. , Adams C. E. 
Published: June 2007

Summary Mean age at vaginal opening was 41 days, range 33–53 days. Bodyweight at weaning and age at vaginal opening were negatively correlated, but there was no relationship between bodyweight and age at vaginal opening. The presence of a male before vaginal opening did not accelerate either the time of its occurrence or first conception. The vaginas of females caged singly from weaning opened earlier than in those kept in groups of 2 or 3.
Studies on Tyzzer's Disease: Acquired Immunity Against Infection and Activation of Infection by Immunosuppressive Treatment
Authors: Fries A. Schaich 
Published: June 2007

Summary The correlation between serum antibody titre and resistance to challenge infection with Bacillus piliformis was studied in naturally infected mice, in experimentally infected but recovered mice, and in mice treated with antigen prepared from infected livers. Irrespective of the way in which the antibodies were acquired resistance to infection was found to be related to the immunofluorescence antibody titre found. Experimentally infected but recovered mice, as well as rats with persistent antibodies to Bacillus piliformis, were given prednisolone in order to activate a possible persistent infection. Bacillus piliformis was detected in the rats, but not in the mice.
Early postnatal physical and behavioural development of degus (Octodon degus)
Authors: Reynolds Thomas J. , Wright John W. 
Published: June 2007

Summary 6 litters of Octodon degus were studied from birth to 10 days of age. Newly-born degus (mean weight 14·6 g) had open eyes, upper and lower pigment, für, and teeth. Within 3–4 hours of birth they were able to walk supporting their full weight, right themselves rapidly, sit upright on their haunches, or rear upright with support, and vocalize. By the 1st or 2nd day, the young animals displayed functional grooming (face washing, hind-paw scratching, rapid head-shake). Solid food was ingested from day 6, although newborns chewed wood chips and 3–day olds gnawed dried faeces. Young degus were tested daily in an open field apparatus and showed increased activity and exploration, with repeated testing while decreasing distress vocalization after the 4th or 5th day. Degus are proposed for the study of developmental topics since their degree of development at birth allows for immediate testing. The degus studied here seem to be more fully developed at birth than those studied in Britain.
'Collaborative' rearing of marmoset triplets
Authors: Hearn J. P. , Burden F. J. 
Published: June 2007

Summary A system of management is described in which all 3 offspring from triplet births of Callithrix jacchus can be successfully reared to weaning. Hand-rearing techniques are applied to the offspring in turn without depriving them of the maternal and family influences necessary for normal behavioural development.
Stress response of rats to handling and experimental procedures
Authors: Gärtner K. , Büttner D. , Döhler K. , Friedel R. , Lindena J. , Trautschold I. 
Published: June 2007

The effects were observed of moving male, adult Han:Sprague rats in their cages or of exposure to ether for 1 min on the plasma concentration profiles of 25 blood characteristics linked with stress and shock reactions. 5 min after the stress serum prolactin, corticosterone, thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, triiodothyronine and thyroxin levels were elevated 150-500% compared with those in blood collected within 100 s of entering the animal room. Heart rate (telemetrically recorded), packed cell volume,, haemoglobin and plasma protein content were 10-20% elevated 2-10 min after cage movement or 2-20 min after ether confrontation over those of controls sampled within 50 s, indicating circulatory and microcirculatory shock reactions. Serum glucose, pyruvate and lactate concentrations rose by 20-100% 1-5 min after cage movement and 1-15 min after ether exposure. Phosphate, calcium, urea, apartate and alanine transferases, alkaline phosphalase and leucine arylamidase were not altered significantly by either stressor, while potassium and bound glycerol fell for 1 min and 5-20 min respectively. The presence of a familiar animal attendant working in the room without touching the cages did not markedly affect the blood characteristics being studied.
Evaluation of a scavenging system for use with inhalation anaesthesia techniques in rats
Authors: Glen J. B. , Cliff G. S. , Jamieson A. 
Published: June 2007

A minimum fresh gas flow of 1 litre per minute per mask and an inspired concentration of 2-3% halothane was required to induce anaesthesia in rats in 1-2 min. Anaesthesia was maintained with an inspired concentration of 1·5-2% halothane. Arterial carbon dioxide concentration increased during anaesthesia and was not reduced by increasing the flow of fresh gas. Using the apparatus described here, halothane vapour concentration in the operator's breathing zone was 5 ppm. Prior to its introduction, levels of 250 ppm had been recorded in a poorly-ventilated animal room.
Embryonic development of NMRI mice: relationship between the weight, age and ossification of embryos
Authors: Fasel Nicolas , Schowing Jean 
Published: June 2007

The time and the order of the appearance of the ossification centres were found to be similar in C3H and NMRI mice. Bodyweight comparisons confirmed these results. Location in the right as opposed to the left uterine horn, or in the upper, middle or lower part, was not found to influence the weight of the embryo. Significant differences in the weight of embryos within the same litter were used in investigating the sequence of ossification in embryos. This should prove useful in comparative morphology and teratology.
Vitamin K deficiency syndromes in warfarin-resistant brown rats (Rattus norvegicus)
Authors: Partridge G. G. 
Published: June 2007

Resistance to the anticoagulant rodenticide warfarin and an increased vitamin K requirement appear to be pleiotropic effects of the gene Rw2. A comparison of pup mortality in F2 ( Rw1 Rw2 × Rw1 Rw2) and backcross ( Rw1 Rw2 × Rw1 Rw1 or reciprocal) matings of wild brown rats in the laboratory revealed significantly greater losses in the F2 litters at 4-8 weeks of age. Some deaths could be attributed directly to haemorrhage resulting from vitamin K deficiency. A newborn warfarin-resistant rat from an F2 litter showed bleeding from the umbilicus and the anus, and died from internal haemorrhage at 18 weeks of age. Another warfarin-resistant male rat dying at the same age had a grossly enlarged skull.
The effect of diet on some parameters measured in toxicological studies in the rat
Authors: Clapp M. J. L. 
Published: June 2007

The bodyweight, food consumption and various biochemical and haematological parameters were measured in, and breeding and histological studies made of, groups of rats fed 6 different diets. All diets acceptably supported reproduction. 1 diet restricted body weight gain by 30%, and increased plasma alanine transaminase activity. Nephrocalcinosis was seen in females fed diets with a calcium: phosphorous ratio of <1. Levels of dietary protein were positively correlated with the incidence of renal pelvic dilatation in offspring at 7 weeks of age.
Polyvalent strain-specific alloantisera as tools for routine genetic quality control of inbred and congenic strains of rats and mice
Authors: Festing Michael F. W. , Totman Peter 
Published: June 2007

Strain-specific polyvalent anoantisera may be obtained by injecting lymphocytes pooled from several different strains into an inbred recipient. 6 sera of this type were produced in rats and 23 in mice. A dye-exclusion microcytotoxic test was used to evaluate the strain specificity of such sera. A total of 663 out of 713 (93·0%) of the tests conformed with expectation, but there were 48 (6·7%) false negative results in which the test failed to detect non-authentic animals. There were also 2 (0·3%) false positive results, in which authentic animals were shown as non-authentic. These were attributed to technical errors. Most false negative results occurred when serum and test cell suspensions matched at the major histocompatibility complex. It was concluded that the use of strain-specific polyvalent immune sera, coupled with a simple immunological test such as the microcytotoxic test, offers a sensitive and quick new method for routine genetic quality control.
Lymphomas associated with a tolerant lymphocytic choriomeningitis virus infection in mice
Authors: Skinner H. H. , Knight E. H. , Lancaster M. C. 
Published: June 2007

On each of 2 occasions when a tolerant lymphocytic choriomeningitis (LCM) virus infection was introduced experimentally by a natural route into breeding stock of the Pirbright P(SD) mouse strain, and a comparison made with genetically identical controls, there was in successive generations an overall 15-fold increase in the incidence of lymphomas. Most of these were recognized clinically after the age of 16 months. The same observation was made in mice of the P(H) strain from which the P(SD) strain had been surgically derived. The finding is interpreted as the activation of an endogenous viral oncogene by the LCM infection. It was concurrently observed that the incidence of mammary tumours in the P(H) strain mice before the age of 16 months was markedly lower in the animals infected with LCM.
Progressive Interval Heuristics for Multi-Item Capacitated Lot-Sizing Problems
Authors: Federgruen Awi , Meissner Joern , Tzur Michal 
Published: June 2007

We consider a family of N items that are produced in, or obtained from, the same production facility. Demands are deterministic for each item and each period within a given horizon of T periods. If in a given period an order is placed, setup costs are incurred. The aggregate order size is constrained by a capacity limit. The objective is to find a lot-sizing strategy that satisfies the demands for all items over the entire horizon without backlogging, and that minimizes the sum of inventory-carrying costs, fixed-order costs, and variable-order costs. All demands, cost parameters, and capacity limits may be time dependent. In the basic joint setup cost (JS) model, the setup cost of an order does not depend on the composition of the order. The joint and item-dependent setup cost (JIS) model allows for item-dependent setup costs in addition to the joint setup costs. We develop and analyze a class of so-called progressive interval heuristics. A progessive interval heuristic solves a JS or JIS problem over a progressively larger time interval, always starting with period 1, but fixing the setup variables of a progressively larger number of periods at their optimal values in earlier iterations. Different variants in this class of heuristics allow for different degrees of flexibility in adjusting continuous variables determined in earlier iterations of the algorithm. For the JS-model and the two basic implementations of the progressive interval heuristics, we show under some mild parameter conditions that the heuristics can be designed to be ϵ-optimal for any desired value of ϵ > 0 with a running time that is polynomially bounded in the size of the problem. They can also be designed to be simultaneously asymptotically optimal and polynomially bounded. A numerical study covering both the JS and JIS models shows that a progressive interval heuristic generates close-to-optimal solutions with modest computational effort and that it can be effectively used to solve large-scale problems.
Aromaticity, π-electron delocalization, and ring currents
Authors: Fowler Patrick W. , Lillington Mark , Olson Leif P. 
Published: June 2007

Abstract
The magnetic criterion of aromaticity is based on the ability of a cyclic system to support a ring current. If the ring current has the diatropic sense, the system is aromatic; if the sense is paratropic, the system is antiaromatic. Attribution of aromaticity ab initio therefore reduces to the calculation and visualization of induced current density. This can be achieved at modest computational cost within the ipsocentric approach, where current density at any point in space is calculated with that point as origin of vector potential. This choice leads to accurate maps of current density and a uniquely simple interpretation in terms of nonredundant orbital contributions governed by translational and rotational selection rules. For example, four-electron diatropicity and two-electron paratropicity are predicted for delocalized forms of [4n+2]- and [4n]-annulenes, respectively. A new application to homoaromatic systems is described. Two model tris-homoaromatics, both neutral molecules, are shown to exhibit a through-space, highest occupied molecular orbital (HOMO)-dominated, four-electron ring current, in a direct analogy with the conventional "aromatic" benzene π-current.
New development of photoinduced electron-transfer catalytic systems
Authors: Fukuzumi Shunichi 
Published: June 2007

AbstractAs an alternative to conventional charge-separation functional molecular models based on multi-step long-range electron transfer (ET) within redox cascades, simple donor-acceptor dyads have been developed to attain a long-lived and high-energy charge-separated (CS) state without significant loss of excitation energy. In particular, a simple molecular electron donor-acceptor dyad, 9-mesityl-10-methylacridinium ion (Acr+-Mes), is capable of fast charge separation but extremely slow charge recombination. Such a simple molecular dyad has significant advantages with regard to synthetic feasibility, providing a variety of applications for photoinduced ET catalytic systems, including efficient photocatalytic systems for the solar energy conversion and construction of organic solar cells.
New mechanisms centered on reactive intermediates: Examples from diazirine and carbene chemistry
Authors: Moss Robert A. , Tian Jingzhi , Chu Gaosheng , Sauers Ronald R. , Krogh-Jespersen Karsten 
Published: June 2007

Abstract
Laser flash photolysis (LFP) of appropriate diazirine precursors afforded the UV spectra of methylchlorocarbene, benzylchlorocarbene, cyclopropylchlorocarbene, and 1-adamantylchlorocarbene. The σ → p transitions of these carbenes were used to directly monitor their reaction kinetics. The unusual and highly reactive N2CO compound, diazirinone, was obtained from the reaction of fluoride ion with p-nitrophenoxychlorodiazirine. Diazirinone fragmented to CO and N2 in a reaction that was exothermic by >90 kcal/mol. Dichlorodiazirine (DCD) was generated by the reaction of chloride ion with p-nitrophenoxychlorodiazirine. Reactions of dichlorocarbene generated from DCD are discussed.
Proton transfer across hydrogen bonds: From reaction path to Schrödinger's cat
Authors: Fillaux François , Cousson Alain , Gutmann Matthias J. 
Published: June 2007

AbstractWe review recent studies of the interconversion mechanism of OH···O hydrogen-bonded centrosymmetric dimers through proton transfer in the prototype crystals of potassium hydrogen carbonate (KHCO3) and benzoic acid (C6H5COOH). The point at issue is whether the proton distributions at various temperatures arise from classical statistical mixtures of tautomers or quantum mechanical superposition states. A related issue is whether it is possible to probe a quantum superposition without inducing decoherence and classicality. We show that neutron diffraction can realize decoherence-free measurements for strictly defined scattering geometries and thus evidence macroscopic quantum correlations. We present a theoretical framework for decoherence-free macroscopically entangled states of the sublattice of protons. The neutron diffraction cross-section of protons is enhanced by a factor of ~45, compared to regular Bragg diffraction, and quantum correlations are observed with remarkable contrast. At elevated temperatures, up to 300 K, quantum correlations are unaffected by proton transfer. The crystal is a coherent superposition of macroscopic tunnelling states, like Schrödinger's cat in a superposition of dead and alive states.
Self-assembly of a nickel(II) pseudorotaxane nanostructure on a gold surface
Authors: Więckowska Agnieszka , Wiśniewska Marta , Chrzanowski Marcin , Kowalski Jarosław , Korybut-Daszkiewicz Bohdan , Bilewicz Renata 
Published: June 2007

Abstract
Tetraazamacrocyclic complexes of NiII and CuII can be used as components of catenanes or rotaxanes showing electrochemically switched intramolecular motion in solution. In our present studies, we modify these compounds with organothiol chains to attach them to the surface of the electrode using the self-assembly method and employ them next as molecular switches, which change conductivity upon applying appropriate potential. The electrochemical properties of these compounds are studied in the solution and, in the case of thiol derivative, immobilized on the electrode surface. The macrocyclic complex of NiII, immobilized on the Au surface, forms the axis of the rotaxane. This compound can be anchored to the surface by one or two thiol groups. The data obtained from scanning tunneling microscopy (STM) experiments using colloidal Au confirm that the orientation normal to the surface dominates. The electrochemical experiments reveal reversible one-electron oxidation of metal center from +2 to +3. The behavior of the electrode modified with the macrocyclic complex of NiII upon immersion in a solution containing bismacrocyclic complex of NiII points to the formation of a new rotaxane-like nanostructure on the surface of the electrode.
Designing novel organic–inorganic frameworks
Authors: Paz Filipe A. Almeida , Klinowski Jacek 
Published: June 2007

Abstract
Crystal engineering of coordination frameworks is a topical and rapidly advancing field, and a variety of entirely new solid materials have been synthesized. We describe the main challenges involved in the hydrothermal approach to these materials using, as an example, cadmium- and zinc-based coordination frameworks. We discuss the unusual crystal architectures of the products, and show that the kind and quality of the resulting crystals are directly controlled by the composition of the ternary reactive mixture and the temperature regime used in the hydrothermal synthesis.