Search

ABSTRACTFailure of anti-Pneumocystis jiroveciprophylaxis with sulfa drugs is associated with mutations within the putative active site of the fungal dihydropteroate synthase (DHPS), an enzyme encoded by the multidomain FASgene. This enzyme is involved in the essential biosynthesis of folic acid. The most frequent polymorphisms are two mutations leading to two amino acid changes (55Trp-Arg-57Pro to 55Ala-Arg-57Ser), observed as a single or double mutation in the same P. jiroveciisolate. In the absence of a culture method for P. jiroveci, we studied potential resistance to sulfa drugs conferred by these polymorphisms by using Saccharomyces cerevisiaeas a model. Single or double mutations identical to those observed in the DHPS domain of the P. jiroveci FASgene were introduced by in vitro site-directed mutagenesis into alleles of the S. cerevisiae FOL1gene, which is the orthologue of the P. jiroveci FASgene. The mutated alleles were integrated at the genomic locus in S. cerevisiaeand expressed by functional complementation in a strain with a disrupted FOL1allele. The single mutation 55Trp to 55Ala conferred resistance to sulfanilamide, whereas the single mutation 57Pro to 57Ser conferred resistance to both sulfanilamide and sulfadoxine. Both single mutations also separately conferred hypersensitivity to sulfamethoxazole and dapsone. The resistance to sulfadoxine is consistent with epidemiological data on P. jiroveci. The double mutation 55Trp-Arg-57Pro to 55Ala-Arg-57Ser conferred on S. cerevisiaea requirement for p-aminobenzoate, suggesting reduced affinity of DHPS for this substrate. This characteristic is commonly observed in mutated DHPS enzymes conferring sulfa drug resistance from other organisms. However, the double mutation conferred hypersensitivity to sulfamethoxazole, which is not in agreement with epidemiological data on P. jiroveci. Taken together, our results suggest that the DHPS polymorphisms observed in P. jiroveciconfer sulfa drug resistance on this pathogen.

Previous reports identified two peptides that mimic the action of neuroprotective proteins derived from astrocytes. These peptides, NAPVSIPQ and SALLRSIPA, prevent neuronal cell death produced by electrical blockade, N-methyl-d-aspartate, and β-amyloid peptide (25-35). In the present study, all d-amino acid peptides of NAPVSIPQ and SALLRSIPA were synthesized and compared respectively to the corresponding all l-amino acid peptides. In rat cerebral cortical test cultures cotreated with 1 μM tetrodotoxin, the d-amino acid peptides produced similar potency and efficacy for neuroprotection as that observed for their respective l-amino acid peptides. Since all these peptides tested individually exhibited attenuation of efficacy at concentrations of >10 pM, combinations of these peptides were tested for possible synergies. Equimolar d-NAPVSIPQ and d-SALLRSIPA combination treatment produced potent neuroprotection (EC50, 0.03 fM) that did not attenuate with increasing concentrations. Similarly, the combination of l-NAPVSIPQ and d-SALLRSIPA also had high potency (EC50, 0.07 fM) without attenuation of efficacy. Combined administration of peptides was tested in a model of fetal alcohol syndrome and in a model of learning impairment: apolipoprotein E knockout mice. Intraperitoneal administration of d-NAPVSIPQ plus d-SALLRSIPA to pregnant mice (embryonic day 8) attenuated fetal demise after treatment with an acute high dose of alcohol. Furthermore, oral administration of d-NAPVSIPQ plus d-SALLRSIPA significantly increased fetal survival after maternal alcohol treatment. Apolipoprotein E knockout mice injected with d-NAPVSIPQ plus d-SALLRSIPA showed improved performance in the Morris water maze. These studies suggest therapeutic potential for the combined administration of neuroprotective peptides that can act through a mechanism independent of chiral recognition.

Specific pyridine-based aldimines and aminals act as chelating ligands towards the RuCpL and RuTpL (Tp = hydrido trispyrazolylborate) fragments giving κ²N,N'-coordinated cyclic imine complexes. Under particular conditions, as elucidated in this paper, these complexes rearrange into cyclic aminocarbene complexes. Thus, the reaction of [RuCp(L)(CH3CN)2]PF6 (L = CH3CN, PMe3, SbPh3) with 1 equiv. of py−N=CHR [R = Ph (phenyl), Fc (ferrocenyl), Np (naphthyl)] affords the cyclic aminocarbene complexes [RuCp(L)(=C(R)NH−py)]PF6, whereas when L = PPh3, PiPr3, and CO the reaction stops at the stage of the imine complex [RuCp(L)(κ²N,N'-py−N=CHR)]PF6. Analogously, [RuTp(COD)Cl] (COD = 1,5-cyclooctadiene) also reacts readily with the imines py−N=CHR (R = Ph, pMeOC6H4, Np) at elevated temperatures to yield the aminocarbene complexes [RuTp{=C(R)NH−py}Cl]. This process may open a new synthetic route for obtaining carbene complexes. The mechanism of the imine−aminocarbene conversion was analyzed by DFT/B3LYP calculations. Accordingly, the operation of a direct 1,2 hydrogen shift can be ruled out; the reaction seems to involve hydrido iminoacyl intermediates resulting from C−H bond activation and deprotonation/protonation steps. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

The bonding modes of 2-aminopyridine apy 1 equiv. with some rutheniumii fragments were studied. In the reaction with RuCpCH3CN31 one acetonitrile ligand is replaced with apy being κ1N-pyridine bonded. This complex is very air-sensitive transforming into dinuclear RuCpμ3-dapy22where dapy is deprotonated apy. On the other hand, RuCl2PPh33 exchanges one phosphine ligand for apy which is coordinated in the κ2N,N′ mode. Similar to 1, the complexes RuCpCH3CN2L(L PMe3, PPh3or CO), also react with apy to give RuCpCH3CNLκ1N-apy. These compounds were reacted with HCCPh with appreciable differences depending on L. While with L CH3CN no clean reaction took place, with L PMe3an η3-allyl carbene is formed with release of apy. With L PPh3or CO, dapy stabilizes a Fischer carbene through chelation. Finally, if 1is reacted with 2-N,N-dimethylaminopyridine dmapy, all acetonitriles are displaced in favor of η6-coordinated dmapy.

ABSTRACTTo determine the stability of pulsed-field gel electrophoresis (PFGE) patterns of methicillin-resistant Staphylococcus aureusin the nosocomial setting, we analyzed isolates from long-term carriers (>1 month) and from patients involved in well-defined nosocomial epidemics. The number of fragment differences between the first isolate and subsequent isolates in long-term carriers showed a bimodal distribution, with one group having 0 to 6 fragment differences and the other group having 14 to 24 fragment differences. The PFGE patterns of isolates involved in epidemics also presented a similar bimodal distribution of the number of fragment differences. Typing these isolates with another molecular method (inter-IS256PCR) showed that isolates of the first group (i.e., with 1 to 6 fragment differences) were clonally related, whereas the second group (with 14 to 24 fragment differences) could be considered genetically different. Among long-term carriers with clonally related isolates, 74 of 84 (88%) of consecutive isolates showed indistinguishable patterns, whereas 10 of 84 (12%) showed related patterns differing by one to six fragments. Moreover, the frequency of apparition of related patterns is higher when the time between the first and the subsequent isolate is longer. During seven nosocomial epidemics lasting from 1 to 15 months, only 2 of 120 isolates (1.7%) showed a pattern which was different, although related, from the predominant one involved in each of these outbreaks.

Abstract. Objective:To prospectively examine the diagnostic accuracy of two‐dimensional transthoracic echocardiography (2‐D echo) in emergency department (ED) patients being evaluated for acute pulmonary embolism (PE). Methods:This was a 14‐month prospective observational trial of a convenience sample of ED patients undergoing evaluation for suspected PE at a suburban teaching hospital. The 2‐D echo was defined as positive if any two of the following were noted: right ventricular dilation, abnormal septal motion, loss of right ventricular contractility, elevated pulmonary artery or right ventricular pressures, moderate to severe tricuspid regurgitation, or visualization of a clot seen in the right ventricle or pulmonary artery. The patient was considered to have a PE if one of the following was positive: a pulmonary angiogram, contrast helical computed tomography, a magnetic resonance angiogram, a high‐probability ventilation/perfusion (V/Q) scan without contradictory evidence, or an intermediate‐probability V/Q scan with ultrasonic evidence of deep venous thrombosis. Results:Of 225 cases identified, 39 met the defined criteria for PE (17%). A 2‐D echo was performed on 124 patients (55%), of whom 27 (22%) had PE. In 20 patients the 2‐D echo had at least two indicators of right ventricular strain; however, only 11 of these patients had confirmed pulmonary embolus. The 2‐D echo had a sensitivity of 0.41 (95% CI = 0.32 to 0.49) and a specificity of 0.91 (95% CI = 0.86 to 0.96). The likelihood ratio positive was a moderately strong 4.4, with a weak likelihood ratio negative of 0.6. Conclusions:Bedside 2‐D echo is not a sensitive test for the diagnosis of PE in ED patients. Positive findings moderately increase the suspicion for PE but are not diagnostic.

Global deployment of vaccines that can provide protection across several age groups is still urgently needed to end the COVID-19 pandemic, especially in low- and middle-income countries. Although vaccines against SARS-CoV-2 based on mRNA and adenoviral vector technologies have been rapidly developed, additional practical and scalable SARS-CoV-2 vaccines are required to meet global demand. Protein subunit vaccines formulated with appropriate adjuvants represent an approach to address this urgent need. The receptor binding domain (RBD) is a key target of SARS-CoV-2 neutralizing antibodies but is poorly immunogenic. We therefore compared pattern recognition receptor (PRR) agonists alone or formulated with aluminum hydroxide (AH) and benchmarked them against AS01B and AS03-like emulsion-based adjuvants for their potential to enhance RBD immunogenicity in young and aged mice. We found that an AH and CpG adjuvant formulation (AH:CpG) produced an 80-fold increase in anti-RBD neutralizing antibody titers in both age groups relative to AH alone and protected aged mice from the SARS-CoV-2 challenge. The AH:CpG-adjuvanted RBD vaccine elicited neutralizing antibodies against both wild-type SARS-CoV-2 and the B.1.351 (beta) variant at serum concentrations comparable to those induced by the licensed Pfizer-BioNTech BNT162b2 mRNA vaccine. AH:CpG induced similar cytokine and chemokine gene enrichment patterns in the draining lymph nodes of both young adult and aged mice and enhanced cytokine and chemokine production in human mononuclear cells of younger and older adults. These data support further development of AH:CpG-adjuvanted RBD as an affordable vaccine that may be effective across multiple age groups.

Eliciting antibodies to surface-exposed viral glycoproteins can generate protective responses that control and prevent future infections. Targeting conserved sites may reduce the likelihood of viral escape and limit the spread of related viruses with pandemic potential. Here we leverage rational immunogen design to focus humoral responses on conserved epitopes. Using glycan engineering and epitope scaffolding in boosting immunogens, we focus murine serum antibody responses to conserved receptor binding motif (RBM) and receptor binding domain (RBD) epitopes following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike imprinting. Although all engineered immunogens elicit a robust SARS-CoV-2-neutralizing serum response, RBM-focusing immunogens exhibit increased potency against related sarbecoviruses, SARS-CoV, WIV1-CoV, RaTG13-CoV, and SHC014-CoV; structural characterization of representative antibodies defines a conserved epitope. RBM-focused sera confer protection against SARS-CoV-2 challenge. Thus, RBM focusing is a promising strategy to elicit breadth across emerging sarbecoviruses without compromising SARS-CoV-2 protection. These engineering strategies are adaptable to other viral glycoproteins for targeting conserved epitopes.

The high orbital eccentricity of the planet around 16 Cygni B may have been induced by the companion star, 16 Cygni A, but only if the stellar binary has sufficiently small periastron distance. The long period of the stellar binary, ?3 × 104yr, implies that less than 1% of the orbit has transpired since its first astrometric measurements in 1830. Therefore, we compute the orbit from the measured instantaneous velocity and position vectors, based on new precise Doppler and astrometric data, along with the Hipparcosparallax. The only unknown parameter is the separation between AB along the line of sight, constrained by the demand that the orbit be bound, which leads to a family of possible orbits for 16 Cygni AB. The physically plausible orbits have 18,200 yr

Based on data from an 18-year follow-up of Wisconsin high school seniors, this paper describes the process of occupational achievement among men and women from labor market entry to mid-life. In contrast to several earlier studies, there are marked sex differences in the acquisition and maintenance of occupational status. The effect of post high school education on the status of first jobs is twice as great among men as among women, and the effect of the status of first jobs on that of current jobs is one-third greater among men than among women. Men gain an average of nine points on the Duncan scale betweentheir first civilian jobs and their jobs at age 36, but women lose an average of more than two points on the Duncan scale. At the same time, sex differences in occupational attainment are not all disadvantageous to women. First jobs of women are six points higher in status on the average than first jobs of men, and when the status of first jobs is controlled, the continuing influence of schooling on occupational status is twice as great among women as among men. Consequently, as others have also found, the total effects of schooling on the occupational statuses of women and men are the same at mid-life. Among the minority of women who remain childless, the process of occupational attainment is more similar to that among men.

The study of the genetic heterogeneity of P. cariniiis complicated by the lack of an in vitro culture system, as well as by the likely occurrence of co‐infections with several special forms or types in a single host. Karyotyping and multilocus enzyme electrophoresis are useful for studies at the evolutionary level. However, these methods require a large number of cells, which prevents their use for the special form infecting humans. DNA sequence analysis of genomic regions is useful to study P. cariniidiversity, both at the evolutionary and epidemiological levels. To type the special form specific to humans, several methods are currently used to detect polymorphism in PCR products of polymorphic regions of the genome: DNA sequencing, type‐specific hybridisations, and single‐strand conformation polymorphism. All these methods still need evaluation. The frequency of potential co‐infections in humans determined by these various methods is different. The differences could be due to methodological problems or to real variations between patient populations, geographical locations and/or prophylaxis regimens. In the future, elucidating the population structure of P. cariniiand the frequency of potential co‐infections is going to be crucial for a better understanding of its epidemiology, and thus for a better prevention of P. cariniipneumonia in humans.

Outpatients followed in an anticoagulation clinic were studied retrospectively to determine the effect of warfarin on the activated partial thromboplastin time (APTT). Twenty-nine patients were studied in part 1 of the trial to determine whether their APTT values were elevated when their prothrombin time (PT) was within 1.5 to 2.5 times the control PT. Part 2 was carried out using the data of 32 patients to determine whether a correlation existed between the degree of elevation of the patients' PT values due to warfarin and the concurrent degree of elevation of their APTT results. Baseline PT and APTT values and a minimum of three concurrent PT and APTT values determined during anticoagulation therapy with warfarin were used. Data were collected by chart review and review of Hematology Department records. Results indicated that a statistically significant difference was evident between the baseline APTT (30.79 sec) and the mean APTT (55.10 sec) when the PT was within the therapeutic range of 1.5 to 2.5 times the control while on warfarin therapy. Good linear correlation was evident (r = 0.821) between the degree of elevation of the PT and the degree of elevation of the APTT for the group. In most cases, a good linear correlation was also evident for individual patients. Routine ordering of concurrent APTT and PT tests for patients receiving warfarin therapy is not needed since the PT alone can be monitored under most circumstances.

• To test the hypothesis that myocardial infarction (MI) size rather than location determines the ventricular response to reperfusion, we studied 69 patients receiving intracoronary streptokinase within five hours of chest pain onset who displayed sustained reperfusion at 8.4±3.4 (SD) days. Twenty reperfusion failures served as controls. There were 31 patients with anterior MIs, 18 of which were estimated to be large based on an ejection fraction (EF) at reperfusion of less than 50%; 14 of 38 patients with inferior MIs also had large MIs. The EF increased at follow-up by 6.4%±2.6% in patients with large anterior MIs and by 8.2%±2.5% in those with large inferior MIs; in contrast, it increased by only 1.8%±2.6% in patients with small anterior MIs and significantly decreased by 5.8%±1.9% in patients with small inferior MIs. Six controls with large MIs (four anterior) displayed no change in EF; in 14 with small MIs (ten inferior), it fell slightly. There were no significant group differences in the number of diseased vessels, residual stenosis, or collaterals. It is concluded that MI size, not site, largely determines the ventricular functional response to early reperfusion; thus, patients with inferior MIs cannot be disqualified on this basis alone for thrombolytic therapy.(Arch Intern Med 1985;145:2188-2193)

This article is an invited critique of Rytina's proposal that canonically weighted scales for detailed occupations be used to assess intergeneratinal occupational persistence. These canonical scales yield higher intergenerational correlations than the Duncan SEI primarily because they capitalize on chance fluctuations in the data used to construct them. Thus, there is no reliable basis for revising previous findings about the relative importance of ascription and achievement in the stratification process. Canonical scaling (and related log-linear and log-multiplicative models) are no more than a useful adjunct to models that locate the sources of intergenerational occupational persistence in the measurable characteristics of occupations and persons.

Although cardiopulmonary bypass support has been increasingly used for high risk coronary angioplasty, few data exist regarding its effects on left ventricular function. Accordingly, in 20 patients changes in left ventricular size, afterload and myocardial function were assessed by continuous hemodynamic monitoring and simultaneous two-dimensional echocardiography during cardiopulmonary bypass-supported high risk angioplasty.

The direct manipulation of coronary blood flow to induce regional myocardial ischemia has been almost entirely limited to experimental animal models. Thus, the detection of ischemia-induced left ventricular dysfunction in human subjects has been generally limited to observations made under conditions of diagnostic loading or during spontaneous clinical events. Percutaneous coronary angioplasty requires repeated interruptions of coronary blood flow for periods as long as 1 minute. The resulting appearance of or increase in ischemia-produced changes in myocardial function were detected by two-dimensional echocardiography in 18 patients undergoing angioplasty of 22 coronary stenoses. Accordingly, left ventricular contraction was studied during 52 episodes of regional coronary blood flow interruption and reperfusion in the process of inflating and deflating the angioplasty balloon.

• To determine whether or not the timing of heparin infusion affects either bleeding or reocclusion following intracoronary streptokinase for acute myocardial infarction, heparin was infused immediately after streptokinase in 89 patients and was delayed for 12 hours in the subsequent 93. Bleeding occurred in 22 immediate-heparin patients and was major in five (one fatal); there were 14 hemorrhages in the delayed-heparin group, all minor. At discharge, reocclusions were observed in 18% (12/68) of immediate-heparin patients, and 11% (3/27) of the latter. Bioassayed fibrinogen levels displayed sustained depression regardless of bleeding for 20 hours after streptokinase; however, defibrinogenation measured by immunoassay was much less striking. This suggests that high levels of fibrinogen degradation products spuriously affect the bioassay of fibrinogen. We conclude that bleeding is related to the anticoagulant effects of fibrinogen degradation products interacting with heparin, and may be largely independent of hypofibrinogenemia. Delaying heparin for 12 hours may decrease the risk of bleeding while little affecting the risk of reocclusion.(Arch Intern Med 1986;146:667-672)

Simultaneous aerosol formation by equilibrium condensation and the migration of the resulting droplets to the cold surface by thermophoresis is studied theoretically for a turbulent pipe flow. The problem is one in which a mixture of a vapor and noncondensable gas flows into a section of pipe where the pipe wall is cooled far below the dew point of the vapor. Because the temperature gradient at the pipe wall decays to zero once the gas travels far enough into the pipe, only some fraction of the droplets formed will deposit on the pipe wall. The equations of energy and diffusion suggest that turbulence leads to a discontinuity in the aerosol (fog) concentration at the boundary between the fog and clear regions. Numerical solutions are obtained for CsOH fog formation and deposition in steam flow—a particular case of current practical interest in water reactor safety. The axial and radial variations of the aerosol and vapor concentrations are displayed graphically, as are the location of the fog boundary as a function of axial distance and the efficiency of deposition as a function of the pipe wall temperature.

The effective thermal conductivity for radiative heat transfer within an optically thick fluid layer undergoing high Rayleigh number convection is derived. This result is combined with available “pure” free-convection heat-transfer correlations to obtain closed-form analytical descriptions of the gross properties of a radiating fluid layer heated internally or from below. These simple solutions compare favorably with recent work in which the governing energy equation incorporating both turbulent heat transport and thermal radiation is solved numerically.

The formation of fog in laminar and turbulent natural convection boundary layers over a cold vertical surface is investigated theoretically under conditions of local equilibrium, using the similarity forms of the boundary layer equations. The ambient medium surrounding the surface is composed of a noncondensable and a condensable vapor component which is present in trace amounts. The deposition of the vapor species in laminar convection over the cold surface is assumed to occur via ordinary Fick diffusion of vapor plus thermophoretic fog particle drift. In turbulent flow these transport mechanisms are reinforced by the eddy diffusion of vapor and fog particles. Turbulence is shown to lead to a discontinuity in the fog concentration at the boundary between the fog and clear regions. Partial agreement is obtained with available data on frost formation on a vertical plate cooled to cryogenic temperatures by assuming that the thermophoretic transport coefficient is about one order-of-magnitude smaller than its theoretical upper limit.

Biases due to measurement errors in structural equation models of the intergenerational transmission of socioeconomic status were asessed by estimating unobserved variable models with data from the remeasurement program of the 1973 Occupational Changes in a Generation-II survey. We found persuasive evidence that reports of social background and achievement variables by nonblack males are subject to strickly random errors, while reports by black males are subject to significant nonrandom error. When measurement errors are ignored for nonblacks, occupational returns to schooling are underestimated by about 15%, the effects of some background variables are underestimated by as much as 22%, and variation in socioeconomic achievements not attributable to education or social origins is underestimated by as much as 27%. Biases appear to be substantially greater for blacks. Consequently, ignoring measurement error exaggerates racial differences in returns to schooling and occupational inequality not attributable to social origins.

This note compares two structural equation models of educational and occupational resemblance among sibling pairs. Each model decomposes the regression of occupational status on schooling into a between-family regression of common factors and a pair of within-family regressions. In model 1, the within-family regressions are writhin-family factors, and in model 2, the within-family regressions are written in the total educatinal and occupational variables. The two models are equivalent when within-family regressions are the same for each member of the sibling pair. Otherwise, they are not equivalent, and the second model has an undesirable logical implication. Under certain conditions, either model may exhibit symptoms of near-underidentification, or it may be underidentified; this problem may be more likely to occur in model 2 than in model 1.

In a 1973 Australian survey, Broom et al. located two distinct subsamples of men in which fathers and sons reported their own status characteristics and those of their sons and fathers, respectively. Inconsistencies between these two subsamples led Broom et al. to infer that "respondents report (perhaps unconsciously) their socioeconomic careers and the careers of their kin in such ways as either to maximize differences between themselves and their sathers or to minimize differences between themselves and their fathers or to minimize differences between themselves and their sons." If true, this would invalidate most stratification research. Reexamination of the Australian data suggests that the paternal and filial reports are not directly comparable. In a sample of Wisconsin men, parental and filial reports of status variables provide unique and direct evidence about the response biases postulated by Broom et al. There is negligible evidence of such biases. Given the relative strengths of the Australian and Wisconsin research designs, we do not believe that further concern about the presence of this type of response error is warranted.

An analysis is made for thermophoretic transport of small particles through a free-convection boundary layer adjacent to a cold, vertical deposition surface. The gas-particle, boundary layer equations are solved numerically for both laminar and turbulent flow. The numerical results indicate that, for a fixed set of boundary conditions and physical properties, the particle concentration at the wall in the laminar flow is very close to that in turbulent flow. A simple expression is suggested relating the particle transport rate to the heat transfer coefficient for the laminar and turbulent flow regimes.

A nonlinear differential equation describing the Doppler velocity profile for blood flow through the mitral valve has been derived. This equation is based on fluid dynamics and a simple, but comprehensive model of atrial and ventricular mechanics. A numerical solution to the equation is described and provides excellent agreement with Doppler velocity curves obtained clinically. One important result of the theory is that in patients with mitral stenosis, the slope of the clinically observed straight-line descent of the velocity profile is proportional to the mitral orifice area and inversely proportional to the atrioventricular compliance.

Because of its greater ease and rapidity of insertion, the percutaneous intraaortic balloon in many institutions has become the primary method for implementing counterpulsation. We report the results and complications of 113 attempted procedures in a variety of clinical settings. We had a high (93.8 percent) insertion success rate. However, our 18.6 complication rate was similar to the experience reported for the surgical method of insertion. Thus, the original anticipation of reduced complications with this method has not been realized in this and other recent reports.

Anguibactin, a siderophore produced by cells of Vibrio anguillarum 775 harboring the pJM1 plasmid, has now been isolated from the supernatants of iron-deficient cultures. This iron-reactive material was purified by adsorption onto an XAD-7 resin and subsequent gel filtration on a Sephadex LH-20 column. The resulting neutral compound produced an ion at m/z 348 in mass spectrometry and contained one sulfur, four oxygen, and four nitrogen atoms as determined by elemental analysis. Its strong UV absorbance and blue fluorescence were suggestive of a phenolic moiety. In colorimetric reactions anguibactin behaved like a catechol. The catechol assignment was supported by the appearance of a new absorption band at 510 nm in the ferric complex and by the appearance of peaks at 1,367, 1,447, 1,469, and 1,538 cm-1 in the resonance Raman spectrum. In addition, the infrared spectrum gave evidence of a secondary amide function, but no free carboxylic acid or hydroxamic acid groups were observed. A third iron-ligating group was suggested by the liberation of three protons during iron binding; mass spectrometry of the resulting material yielded a molecular ion characteristic of a 1:1 complex of ferric anguibactin. The purified anguibactin exhibited specific growth-promoting activity under iron-limiting conditions for a siderophore-deficient mutant of V. anguillarum 775(pJM1). A novel structure for anguibactin was indicated by the failure of a large number of known siderophores and synthetic chelators to yield a similar type of specific cross-feeding in the V. anguillarum bioassay.

In the short run the war will generate a cyclical movement of vital phenomena in which the birth rate, the rate of natural increase, the rate of populaton growth, the marriage rate, and the divorce rate will pass successively from peak to trough to peak with preparation for, participation in, and cessation of hostilities. During the cyclical movement of these phenomena, military mortality may be expected to increase greatly and, then, to drop abruptly with the close of the war. The effects of the war on the population to date have demographic scars which will have far-reachin long-run effects on the population of the United States; namely, gaps in the age structure of the nation-"hollow classes"; a surplus of women of marriageableage; an appreciable number of disabled men; and a distorted internal distribution of population produced by hurried preparation for war. These effects, in combination with the disturbance of human motivation, the breaking of the "cake of custom," attendant social unrest, widespread diffusion of contraception, and the uncertainty of the future will probably accelerate the downward trend of fertility and decelerate the rate of national population growth. It may be expected that population problems will be among the major problems of post-war adjustment.

Between 1930 and 1940 the population growth of the nation declined markedly with the disappearance of net foreign immigration and with continued decline in natural increase. The decrease in the rate of growth of population in the South was less than that in the North of the West. The balance of age-specific birth and death rates shifted so as to fall below the critical point of population replacement. The rate of urban growth decline greatly, to a point barely exceeding that of rural growth, while the rural-farm population remained practically stationary and the rural-nonfarm population increased relatively rapidly. Metropolitan districts continued to grow more rapidly in outlying areas than in central cities. The population of the nation continued to age, decline somewhat in sex ratio, but changed very little in racial composition. The number and proportion of foreign-born white persons in the United States decreased substantially.

In a contextual analysis it is found that students in schools with high sex ratios have higher educational aspirations than students in schools with low sex ratios (i.e. high male-female ratios) in a population of white high-school senior in Davidson County, Tennessee. The effect of sex-ratio context persists when sex, intelligence, and father's education are controlled. The "consexual effect" is interpreted as a consequence of anticipatory socialization. The contextual interpretation is the exposed as speculative, artifactual, and substantively trivial. Covariance analysis and dummy-variable regression analysis are advocated as more suitable techniques for the measurement and interpretation of differences among groups.

Labor-force rates of older men declined during the last half-century, while those for older women increased. Worker rates for both sexes, however, increased between 1940 and 1950 as a result of the war. In the postwar period, after declines in older worker rate which demobilization, the labor-force participation of older women increased with the Korean incident, while older men resume the war-interrupted trend toward retirement at age 65 and over. Older workers have higher month-to-month changes in labor-force participation than do all workers. Increased expectation of life and decreased expectation in the labor force have, since 1900, greatly increased expected years in retirement for males.

Demography may be conceived as consisting of two facets, demographic analysis and population studies. The former is concerned only with the study of population size and composition and components of variation and change; the latter, with the interrelationships of population and other systems of variables of which the sociological constitute but one set. Population study affords the sociologist the opportunity to work with quantified variables which provide some bechmark against which to work with other sets of variables. Demography, although a multiscience discipline, can contribute to the central interests of sociology and, in return, gain from study of the interrelations of demographic and sociological variables.

Statistics for all "gainful workers" in the United States were reported in the decennial census from 1870 to 1930. In the 1940 census the "labor force" concept was adopted in lieu of the "gainful worker" approach, and simultaneously a monthly sample series of statistics on the "labor force" was initiated. The change in concept from "gainful worker" to "labor force" and in methods of measurement within the framework of each concept affect the comparability of the data. Several splices have been effected, however, within the "gainful worker" series, within the "labor force" series, and between the series which permit analysis of changes and trends in the size and composition of the nation's labor supply.