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We consider the following question. When is there a compactification $ {G_0}$G (recall that a compact group $ {G_0}$compactification of G if there is a continuous homomorphism $ \phi :G \to {G_0}$ is dense in G) with continuous homomorphism $ \phi :G \to {G_0}$ $ \{ {g_\nu }\} $G if and only if $ \{ \phi ({g_\nu })\} $? Such a compactification $ {G_0}$D-compactification of G. We obtain a solution to this problem and thereby generalize to locally compact groups some results of Berg, Rajagopalan, and Rubel concerning D-compactifications of locally compact abelian groups.

Wild-type and gene 3 mutant filamentous phage stocks, containing different relative amounts of multiple-length particles, were treated exhaustively with DNase and then were highly purified. The phage DNA was extracted and examined by electron microscopy. In all cases, about 0.03% of the molecules were circular dimers. 3H-labeled phage DNA was separated as to size by sedimentation in a preformed CsCl density gradient. Individual fractions were then examined in the electron microscope, and the percentage of linear and circular monomer and dimer DNAs was determined. A peak of double-length, circular molecules (with the expected sedimentation constant of 38S) was found ahead of the 24Smonomer peak. The double-length molecules had been purified 65-fold. As previously found for single-stranded DNA, the contour length of these molecules was strongly dependent upon ionic strength. Possible artifacts were ruled out, and it was shown that the double-length molecules arose from phage particles.

Transfection of Escherichia colispheroplasts by native T5 phage DNA was not affected by treatment with polynucleotide ligase. Denatured T5 phage DNA infectivity, only 0.1% of the native DNA level, was increased slightly by polynucleotide ligase treatment. Renatured T5 phage DNA infectivity was also increased slightly by polynucleotide ligase treatment. To form an infective center with rec+spheroplasts, 1.6 to 2.1 native T5 phage DNA molecules were required; however, 1.4 T5 phage DNA molecules were required to form an infective center with recA-B-spheroplasts, and one molecule was sometimes sufficient for rec B-spheroplasts. Polynucleotide ligase treatment of T5 phage DNA had no effect on these parameters. Thus, the single-strand interruptions of T5 phage DNA are probably not essential to the survival of the parental T5 phage DNA, and T5 phage DNA, especially the denatured form, is highly sensitive to some nucleases in E. colispheroplasts.

Simultaneous, continuous recordings of tympanic and esophageal measurements of body temperature were obtained during anesthesia and surgery. Their patterns were found mutually consistent in the clinical situations as studied. Rectal patterns were abandoned as unpredictable in their relation to temperature in the cranium or at the crossroads of central circulation. Tympanic was the only measurement with unequivocally defined location of insertion. With the other methods a reproducible position could not be reached, maintained, or restored. In cleanliness (dry site and disposable probe); sterility; and minimum inconvenience, embarrassment or discomfort to patients, surgeons or physicians and medical personnel, men or women tympanic thermometry was superior to esophageal and rectal. It was never found to be out of place, and rarely contraindicated, while contraindications with rectal or esophageal measurements were frequent.

Quantitative mechanisms that regulate normal temperature and determine its clinical aberrations have been found with the methods of gradient calorimetry and tympanic thermometry. Homeostasis is achieved by warm-sensitive neurons of a "human thermostat" or "temperature-eye" in the anterior portion of the hypothalamus. These fire and excite sweating and vasodilatation for heat loss when their temperature exceeds a sharply determined set point near 37 C (98.6 F). Similar warm-sensitive neurons inhibit, through a synaptic station in the posterior portion of the hypothalamus, the metabolic response to cold which is excited by cold-receptors of the skin firing from thresholds at 33 to 35 C (91.4 to 95 F). Pyrogens depress or extinguish firing of central thermoreceptors. The set point is shifted. Fever develops. These findings provide a basis for the understanding of clinical temperature, and the tool for its reliable measurement—tympanic, not rectal thermometry.

Under proper conditions, one infective center was obtained for 3 × 108molecules of P22 phage deoxyribonucleic acid (DNA) when lysozyme-ethylenediaminetetraacetic acid spheroplasts of Escherichia coliwere transfected in the presence of 25 µg of protamine sulfate per ml. A 3- to 50-fold B-specific and K-specific E. colirestriction of the incoming P22 DNA was observed. When P22 DNA-infected E. colispheroplasts were plated with infertile rLT+mLT+Salmonella typhimuriumindicator, an additional 70-fold restriction was observed. In the presence of protamine sulfate, penicillin spheroplasts of S. typhimuriumSB1330 could be transfected b P22 DNA with efficiencies sometimes approaching those obtained with the E. colispheroplasts; thus, facilitation of transfection by protamine sulfate is not limited to E. colior to lysozyme-ethylenediaminetetraacetic acid spheroplasts. The application of these results to studies of transfection among other genuses and to studies of in vitro host-controlled restriction and modification for the two loci in S. typhimuriumand the one locus in E. coliis discussed.

We prove a general theorem on the completeness of the eigenvectors of linear operators in a Banach space. We then derive asymptotic estimates for the Green's functions of two-point boundary value problems which allow us to apply the above theorem to a wide class of such problems in the spaces .

We investigate the extent to which the eigenfunction expansions arising from a large class of two-point boundary value problems behave like Fourier series expansions in the norm of . We obtain our results by relating Green's function to the Hilbert transform.

The only compound which fully replaced protamine sulfate in facilitating transfection of Escherichia colispheroplasts by phage DNAs was spermine; poly-l-lysine, poly-l-arginine, DEAE-dextran, histones, and many other polyamines were only slightly effective. Higher-molecular-weight compounds were effective at lower concentrations, and each compound had a sharp concentration optimum. The specificity of the facilitation of transfection is discussed in light of Leonard and Cole's (1972) isolation of a polyamine- or protamine-like, natural competence factor from Streptococci. By standardizing growth conditions for spheroplast cultures, storing spheroplasts in minimal medium, and adding both protamine sulfate and polyamines to spheroplasts, reproducible competence levels were obtained. Thus, 95% of all spheroplast preparations gave efficiencies of transfection between 10-3and 3 × 10-4for lambda DNA; between 10-6and 3 × 10-8for T7 DNA; and between 3 × 10-6and 10-7for T5 phage DNA. The stability of the spheroplasts was extended from 10 h to between 2 and 5 days, depending on the DNA used for transfection.

The change of infectivity of phage DNAs after heat and alkali denaturation (and renaturation) was measured. T7 phage DNA infectivity increased 4- to 20-fold after denaturation and decreased to the native level after renaturation. Both the heavy and the light single strand of T7 phage DNA were about five times as infective as native T7 DNA. T4 and P22 phage DNA infectivity increased 4- to 20-fold after denaturation and increased another 10- to 20-fold after renaturation. These data, combined with other authors' results on the relative infectivity of various forms of fX174 and lambda DNAs give the following consistent pattern of relative infectivity. Covalently closed circular double-stranded DNA, nicked circular double-stranded DNA, and double-stranded DNA with cohesive ends are all equally infective and also most highly infectious for Escherichia colilysozyme-EDTA spheroplasts; linear or circular single-stranded DNAs are about 1/5 to 1/20 as infective; double-stranded DNAs are only 1/100 as infective. Two exceptions to this pattern were noted: lambda phage DNA lost more than 99% of its infectivity after alkaline denaturation; this infectivity could be fully recovered after renaturation. This behavior can be explained by the special role of the cohesive ends of the phage DNA. T5 phage DNA sometimes showed a transient increase in infectivity at temperatures below the completion of the hyperchròmic shift; at higher temperatures, the infectivity was completely destroyed. T5 DNA denatured in alkali lost more than 99.9% of its infectivity; upon renaturation, infectivity was sometimes recovered. This behavior is interpreted in terms of the model of T5 phage DNA structure proposed by Bujard (1969). The results of the denaturation and renaturation experiments show higher efficiencies of transfection for the following phage DNAs (free of single-strand breaks): T4 renatured DNA at 10-3instead of 10-5for native DNA; renatured P22 DNA at 3 × 10-7instead of 3 × 10-9for native DNA; and denatured T7 DNA at 3 × 10-6instead of 3 × 10-7for native DNA.

The addition of 25 µg of protamine sulfate per ml to lysozyme-ethylenediamine-tetraacetic acid spheroplasts of Escherichia colistimulates transfection not only for T1 phage deoxyribonucleic acid (DNA; Hotz and Mauser, 1969) but also for the following phage DNA species: lambda, 10,000-fold to an efficiency of 10-3infective centers per DNA molecule; fX174 replicative form, 300-fold to an efficiency of 5 × 10-2; fd replicative form, 300-fold to 10-6; T7, 300-fold to 3 × 10-7. Three native phage DNA species were not infective at all in the absence of protamine sulfate but were infective in the presence of protamine sulfate with the following efficiencies: T4, 10-5; T5, 3 × 10-6; and P22, 3 × 10-9. The effect of protamine sulfate is specific for double-stranded DNA. The application of infectivity assays to the study of phage DNA replication, recombination, prophage integration, prophage excision, and interspecies transfection are discussed.

Die Wärmetönung der Reaktion ATP4– + H2O → ADP3—+ HPO42-– + H+ wurde mit Myosin als Ferment bei pH8,0 gemessen. Nach Abzug der je nach dem Puffersystem ganz verschiedenen Neutralisationswärme des Protons, die wir getrennt gemessen haben, bleibt für die Spaltung der „energiereichen Phosphatbindung“ AH = — 4800 cal. Folgerungen aus diesem Ergebnis — verglichen mit klassischen Annahmen von ungefähr — 12 000 cal — werden kurz besprochen. Prinzip und Leistung der hier erstmals angewandten mikrokalorimetrischen Methode werden beschrieben.

An extended statement of chemical equilibrium calls for consideration of the integral ∫T0 ΔCP dT, in addition to T ∫T0 ΔCp/T dT (= T ΔST0) and ΔHT0—the classical terms of the equation −RTlnK = ΔHT0 = T ΔST0. The integral ∫T0 ΔCP dT is not negligible for macromolecules and particularly biopolymers, and its direct experimental determination at all temperatures down to 0 K is therefore indispensable for thermodynamic understanding of the objects of molecular biology.