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We analyzed time-series abundances of San Joaquin kit fox estimated during 1983-95 on the Naval Petroleum Reserves in California (NPRC). For the analysis, we modified a model of density-dependent, stochastic population growth to include the lagged effects of a weather covariate (vegetation growing season rainfall). Without the covariate in the model, a statistical test failed to detect significant density dependence in fluctuating kit fox abundances. However, when the covariate was added, strong density dependence was detected. According to an information-theoretic model-selection index, the model with both density dependence and rainfall is far superior to the models that result from deleting one or more of these factors. The 2-year time lag in the response of kit fox abundances to changes in rainfall is consistent with biological expectations of how rainfall affects habitat carrying capacity for kit fox. An additional covariate, a coyote abundance index, failed to improve the model. A population viability analysis (PVA) performed with the combined density dependence-rainfall model suggests that the San Joaquin kit fox on NPRC could face a risk of up to 52% of falling to low levels within 20 years.

Graph models play an important role in floor-plan design. In this paper the relations between the various models are investigated. Useful graph-theoretical facts are presented in this context, and their application is discussed. Special attention is given to the implications of structural restraints, for the models as well as for the applications, geometrical optimization and global routing in particular.

A new inner loop criterion for simulated annealing, derived from information theory, is proposed. It depends on the explicitly known transition probabilities of the Markov chain, and therefore measures a dynamic property of the system. The criterion adapts the number of attempts to the problem size, to the control parameter t, and to the landscape of the problem.

In this paper a fast algorithm for placing modules is presented. It gradually transforms a graph structure into a highly packed placement. The positioning of the modules is such that subsequent wiring procedures can be kept simple and total interconnection length can be relatively small. Restrictions on the shapes of the concerned modules are much weaker than those imposed by algorithms with for the rest comparable potency. In an example the algorithm is applied to bipolar integrated circuits with one wiring layer.

Current theories relating the present distribution of ABO blood group frequencies to the selective action of habits of diet and to past screening by specific infectious diseases are open to question on several counts. Aboriginal diet areas in the New World fail to correlate geographically with ABO frequency as postulated. A considerable body of evidence contradictory to the hypothesis of selection by pestilence also exists. Blood group specificity, however, can be shown to figure in several areas of immunological significance. Recent serological studies indicate that former concepts relating to sites of ABH mucopolysaccharide deposition as well as to loci of active antibody formation and protection must be broadened alike. Antibodies in the form of IgA globulins, locally produced in lymphoid tissues, constitute a peripheral system of defense for the protection of mucous membranes. Studies on salivary antigens and antibodies indicate annual fluctuations in levels of production, with corresponding cycles of...

The wiring problem is usually transformed into a graphtheoretical analysis-synthesis problem. For a practical algorithm it is necessary that certain constraints are taken into account in the construction of the respective graph. These constraints originate from the desire to place terminals—eventually in a previously determined sequence—at the periphery of the board or the wiring layer of an integrated circuit (IC). For printed boards we can also have some demands regarding the sequence of contacts and the side on which the components have to be placed. The purpose of this paper is to show how these requirements, which are indispensible for a proper printed board layout, can be examined. Some of these requirements have not appeared in literature before. The inquiry consists of two separate tests, each eventually combined with modification steps. The details of these modifications are not a subject of this paper. In the last section the content of this paper is compared with other publications in this field.

When Boyd and Boyd (’33) and Candela ( ’36) first demonstrated the possibility of the ABO blood typing of aged human bone and tissues, anthropologists were quick to realize the potential value of such data for historical studies of human populations. It was, in fact, this appealing potential which encouraged the profession to have greater faith in the reliability of such tests than was actually warranted. Boyd and Boyd (’39), using 14 known autopsy samples up to five years old, achieved typing results which they called “encouraging but not as conclusive as would be wished for unknown material’’ (p. 424). When Candela ( ’40) successfully typed a portion of their material, doubts were somewhat relieved. But an element of uncertainty remains. In the first place, the growing literature of serological research leads to a conception of the blood group ABO polysaccharide-polypeptide antigens as substances immensely stable under some conditions, but contrastingly fragile under others. In the second place, the method employed in bone typing is not sufficiently exact or specific to meet the requirements of the problem. The several shortcomings of this method will be discussed below. When the Laboratory of Physical Anthropology was first set up at the University of Michigan under sponsorship of the Venner-Gren Foundation, we secured over 40 bone samples from individuals of known blood type at autopsy. These have been tested after aging by means of the standard inhibition

In chapter 5 we derived that the probability that an annealing chain has s as its current state will go asymptotically to δ(s, t), the corresponding value of the equilibrium density. Nothing was said however about how fast these probabilities will approach the equilibrium density. Yet it is necessary to know a priori when the actual density is close enough to the equilibrium density to change the value of the control parameter and to start with another chain. In this chapter we want to address that problem.

In this chapter we review the matrix theory used in this book. The purpose of the first section is to introduce the notation and to call to memory results derived in any core curriculum with a basic matrix theory course. The other three sections are small excursions to obtain theorems often not included in such a course. First the fact that every matrix is similar to a matrix in pseudo-diagonal normal form is established. It is the pivotal theorem in the convergence proof for annealing chains which is given in chapter 3. Another fact used in that proof is Gershgorin’s theorem. Its statement and proof is at the end of the third section. That section is mainly devoted to the convergence of matrix expressions and since norms are useful concepts in that context they are introduced there. That section completes the preparation for the next chapter. The definite integral obtained in the fourth section of this chapter is not used before chapter 6. It is included in this chapter because its derivation heavily depends on matrix theory, and quadratic forms in particular.

The main goal of this chapter is to obtain the result at the end of section 6.3 which is part of the basis for the initialization of annealing as described in section 8.1. On the way to this result we formally define some density functions that are going to be used in chapter 7. After all this effort to obtain theorem 6.14 it is only a small step to the special case of the central limit theorem of section 6.4. This chapter is therefore the background of much that is in chapter 7 and the proof of theorem 8.2. The presentation there is such that it can be read without going through the details of this chapter. These results are achieved by using the characteristic function of a random variable. In section 6.1 this function is defined and some of its more important properties are derived.

The goal of the annealing algorithm is to find a state s with e(s) close to e(s0). The chain would be almost all the time in such a state after reaching equilibrium for a very low value of the control parameter t, but it would take a huge number of steps to reach and detect that situation. For very high values of t the chain will be almost immediately in equilibrium. Also to reestablish equilibrium from an equilibrium situation at a slightly different t can be done in relatively few steps, because changes in the equilibrium density can be made arbitrarily small by keeping the changes in t small enough. The algorithm therefore performs the annealing chain for several in general decreasing, values of t, each time of course with a limited number of steps, and thereby reducing the space accessibility by confining the chain more and more to states hopefully close to a global minimum. The decrements in t and the number of steps per value of t are the parameters that characterize the schedule.

Adult male rats were exposed to dieldrin-contaminated rations. The hydroxylation of benzpyrene (AHH) and hydration of styrene oxide (EH) by the hepatic microsomal fraction were followed. At dieldrin levels of 5 to 25 ppm for one week, the EH activity increased from 19% to 115% above control levels respectively. Animals exposed to 25 ppm developed elevated EH activities after a few days, with a maximum increase of 2.5 times control levels after two weeks. AHH activity was not elevated over control levels at any dose or time studied. Slight but significant increases in levels of cytochrome P-450 were observed. Pentobartibal sleeping time was decreased to 61% of control levels after exposure to 20 ppm dieldrin-contaminated food for 7 days. Two days of intraperitoneal administration of technical grade dieldrin, analytical grade dieldrin and analytical grade aldrin gave similar increases in EH activity within this group. Again, no changes in AHH activity were seen.

2 people from different families had high levels of serum-thyroxine (T4) and a high free T4 (FT4) index but a normal serum triiodothyronine (T3) and serum-reverse-T3 (rT3). The abnormal serum thyroid hormone profile appeared to be inherited in an autosomal dominant manner. Serum-FT4 in affected relatives was normal. The increases in serum-T4 and FT4 index are explained on the basis of an observed increase in affinity of T4 for thyroxine-binding globulin, thyroxine-binding prealbumin, and albumin. The FT4 index did not reflect the true concentration of circulating free T4 in these cases. Thyroid function in the propositi was normal and the results of T4, T3, and rT3 kinetic studies accorded with increased binding of T4 by serum proteins and normal binding of the other iodo-thyronines. This "euthyroid high total T4, normal T3 syndrome" should be kept in mind during diagnostic evaluation of thyroid function.

1 The Annealing Algorithm: A Preview.- 1.1 Combinatorial optimization.- 1.2 Moves and local minima.- 1.3 Hill climbing.- 1.4 Simulated annealing.- 1.5 Applications.- 1.6 Mathematical model.- 1.7 Discussion.- 2 Preliminaries from Matrix Theory.- 2.1 Matrices. Notation and basic properties.- 2.2 Pseudo-diagonal normal forms.- 2.3 Norms and limits of matrices.- 2.4 Quadratic forms.- 2.5 Discussion.- 3 Chains.- 3.1 Terminology.- 3.2 Linear arrangement, an example.- 3.3 The chain limit theorem.- 3.4 Reversible chains.- 3.5 Discussion.- 4 Chain Statistics.- 4.1 Density Functions.- 4.2 Expected values.- 4.3 Sampling.- 4.4 Maximum likelyhood densities.- 4.5 Aggregate functions.- 4.6 Discussion.- 5 Annealing Chains.- 5.1 Towards low scores.- 5.2 Maximal accessibility.- 5.3 The acceptance function.- 5.4 Properties of annealing chains.- 5.5 Discussion.- 6 Samples from Normal Distributions.- 6.1 Characteristic functions.- 6.2 Quadratic forms and characteristic functions.- 6.3 Sampling distributions.- 6.4 Asymptotic properties of sampling distributions.- 6.5 Discussion.- 7 Score Densities.- 7.1 The density of states.- 7.2 Weak control.- 7.3 Strong control.- 7.4 Three parameter aggregates.- 7.5 Discussion.- 8 The Control Parameter.- 8.1 Initialization.- 8.2 Decrements in the control parameter.- 8.3 A stop criterion.- 8.4 Proper convergence.- 8.5 Discussion.- 9 Finite-Time Behavior of the Annealing Algorithm.- 9.1 Rate of convergence of chains.- 9.2 Minimum number of iterations.- 9.3 Finite-time optimal schedules.- 9.4 Discussion.- 10 The Structure of the State Space.- 10.1 Chain convergence.- 10.2 The topography of the state space.- 10.3 The set of moves.- 10.4 Global convergence.- 10.5 Discussion.- 11 Implementation Aspects.- 11.1 An implementation.- 11.2 The selection function.- 11.3 Other speed-up methods.- References.

Many problems that arise in practice are concerned with finding a good or even the best configuration or parameter set from a large set of feasible options. Feasible means that the option has to satisfy a number of rigid requirements. An example of such an optimization problem is to find a minimum weight cylindrical can that must hold a given quantity of liquid. Assuming the weight of the empty can to be proportional to its area, the problem can be formulated as finding the dimensions of a cylinder with a volume c, and the smallest possible perimeter: minimize $$ 2\pi rh + \pi {r^2} $$ while $$ \pi {r^2}h = C $$ and r > 0 The formulation consists of a function to be minimized, the objective function, and a number of constraints. These constraints specify the set of feasible options, in this case the parameter pairs (r,h) that represent cylinders with radius r, height h, and volume c. Feasibility requirements are not always given as explicit constraints. In this example the volume constraint could have been substituted into the objective function.

Continuous exposure to inhibitory concentrations of methotrexate produces distinct rates of steady-state growth of murine leukemia L1210 and human leukemia CCRF-CEM cells in culture. Addition of thymidine to the medium produces reversal (6 to 40%) of this steady-state growth rate inhibition. This study utilized combinations of methotrexate and thymidine for an evaluation of the accompanying relationship between steady-state growth rate and changes in the ribo- and deoxyribonucleoside triphosphate pools. In L1210 cells exposed to methotrexate alone, the deoxythymidine 5'-phosphate (dTTP) pools decreased, whereas deoxyadenosine 5'-triphosphate, deoxyguanosine 5'-triphosphate, and deoxycytidine 5'-triphosphate (dCTP) remained relatively constant up to 70% inhibition of growth rate, with dCTP at a constant 112% of controls. The corresponding ribonucleoside triphosphates decreased only slightly. With the combination of methotrexate and thymidine resulting in up to 40% inhibition of growth rate, there was also a decrease in the dTTP pool while the other deoxyribonucleoside triphosphates remained relatively constant, and the corresponding ribonucleoside triphosphates again decreased only slightly. The dCTP pool was reduced to a constant 42% of control comparable to that produced by thymidine alone. With greater than 40% (with thymidine) or 70% (without thymidine) inhibition of growth rate, all pools decreased, but only dTTP was substantially reduced in proportion to the growth rate inhibition caused by methotrexate. The dTTP pool became depleted in spite of the presence of exogenous thymidine. Evaluation of CCRF-CEM cells indicated that inhibition of growth rate and nucleotide pool perturbations by methotrexate were similar to those observed in L1210 cells. However, in the presence of thymidine, inhibition of growth rate appeared related to decreased pools of dCTP, deoxyadenosine 5'-triphosphate, and deoxyguanosine 5'-triphosphate, rather than dTTP as was observed for L1210 cells. Hence, mammalian cells were capable of responding in a differential fashion to pharmacological perturbations, and this capacity may play a role in determining therapeutic selectivity. Since the ribonucleoside triphosphate decreases were slight and relatively uniform during methotrexate-induced perturbations, the deoxyribonucleoside triphosphate pools appear to be more directly related to inhibition of growth rate. The results are consistent with the concept that slight imbalances in the deoxyribonucleoside triphosphate pools dramatically inhibit DNA synthesis, as mediated through their interaction with DNA polymerase.

Es wird berichtet uber 450 Patienten, die im Alter von 80–103 Jahren wegen verschiedener allgemeinchirurgischer Erkrankungen in der Zeit von 1958–1968 in der Chirurgischen Universitatsklinik Dusseldorf (Direktor: Professor Dr. Dr. Dr. E. Derra) in Allgemeinnarkose — z.T. mehrmals — operiert wurden.

An der Hand klinischer Beobachtungen wird der typischen, doppelseitigen, von den Spitzen ausgehenden Lungentuberkulose eine vorwiegend einseitige, von den Hilusdrusen ausgehende Verlaufsform der Lungentuberkulose gegenubergestellt.

Gustafson and co-workers (1973) in a study on Escherichia coli show that the chloramphenicol inhibition on protein synthesis opens also the outer membrane barrier to crystal violet. There is evidence that crystal violet and chloroxylenol, two hydrophobic molecules (Nikaido, 1976; Kropinski et al., 1978) cross the outer membrane of Pseudomonas aeruginosa by a particular pathway. These observations were made in our study on the sensitivity of Pseudomonas aeruginosa to antibacterials according to the growth conditions. The data show a resistance to chloroxylenol and crystal violet when the organism is grown in tryptic soy broth (T.S.B. Difco) and a sensitivity to these products when the bacteria is grown in brain heart infusion (B.H.I. Difco) (Devleeschouwer et al., submitted). It seemed thus interesting to look if a pretreatment of the strain with chloramphenicol would restore the sensitivity to chloroxylenol and crystal violet of the bacteria grown in T.S.B.