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Our objectives were to evaluate a fixed-time AI (FTAI) protocol versus a modified estrus detection with fixed-time AI (MTAI) protocol on estrus synchronization and pregnancy rates. Angus-based, crossbred heifers (n = 971; 346 ± 14 kg) were estrus synchronized via a melengestrol acetate-prostaglandin F2α (PG) protocol. An estrus detection aid (patch) was applied at PG injection. Each heifer was assigned a patch score (reflecting the amount of rub-off coating removed) at AI to reflect estrus status. At 72 h following PG, FTAI heifers received a 2-mL gonadotropin-releasing hormone injection and were inseminated. Estrus was detected in MTAI heifers at 58 and 70 h after PG. Approximately 72 h after PG, MTAI heifers were inseminated in the following order: heifers in estrus at 58 h after PG, heifers in estrus at 70 h after PG, and heifers not appearing in estrus at either observation. Heifers not expressing estrus received gonadotropin-releasing hormone at AI. Pregnancy was determined via transrectal ultrasonography 51 d after AI. In both treatments, heifers exhibiting estrus had greater (P < 0.01) AI conception rates than heifers not expressing estrus (71 and 66 ± 5% for FTAI vs. MTAI, respectively, vs. 47 and 53 ± 9% in nonestrus heifers for FTAI and MTAI, respectively). However, overall AI pregnancy rate (62 ± 5%) and final pregnancy rates were similar between treatments (P ≥ 0.49; 97 ± 3%). Similar AI pregnancy rates were achieved without the added labor of estrus detection.

Transposon mutagenesis was used to isolate insertion mutants of the photosynthetic bacterium Rhodobacter capsulatus which were unable to grow under aerobic conditions in the dark on malate, succinate or fumarate as sole carbon sources. Of five mutants isolated, all were deficient in C

We report the characterisation of gated optical image intensifiers for fluorescence lifetime imaging, evaluating the performance of several different prototypes that culminate in a new design that provides improved spatial resolution conferred by the addition of a magnetic field to reduce the lateral spread of photoelectrons on their path between the photocathode and microchannel plate, and higher signal to noise ratio conferred by longer time gates. We also present a methodology to compare these systems and their capabilities, including the quantitative readouts of Förster resonant energy transfer.

An inherent shortcoming of rectifiers designed using standard CMOS devices is poor low input power performance. It is shown that this can be overcome through the use of intrinsic devices with close to zero-threshold voltage available in a 0.25 μm silicon-on-sapphire (SOS) CMOS process. A novel complementary bridge rectifier structure based on a combination of cross-connected and diode bridge rectifier topologies is introduced to avoid the excessive leakage current incurred through the use of intrinsic devices. A design strategy which maximizes efficiency and produces an input impedance which will interface well with the inductive coil type antennas used in biomedical implants is presented for this new rectifier type. The fabricated rectifier achieves a 1 μW DC output power for an input power of -26.5 dBm at 100 MHz. A peak measured power conversion efficiency of 67% is achieved at 100 MHz, but more importantly >;30% PCE is attained for a wide output power range which reaches as low as -40 dBm. At the target 1 μW output power a PCE of 44% was achieved.

On 19 December 2008, a large portion of the S-shaped, steel-framed walkway under construction at the Atlanta Botanical Gardens suddenly collapsed during concrete placement operations. The approximately 575 ft long cable-stayed canopy bridge was designed to be supported by four masts along the curved spline segments and two opposing inclined columns at the transitional straight spline segments. At the time of collapse, the walkway structure was supported on temporary shoring tower frames and helical piles. A detailed study of movement and structural behavior was used to investigate the cause of collapse. Construction photos made it possible to compare erected locations of shoring tower frames and grillage members with their post-collapse locations and stacked configurations. Spline impact marks on the ground and shoring members below showed varying degrees of post-impact translation at points along the length of the collapsed walkway structure. Type and directionality of bolt failures at spline beam splices and abutments, and angles of inclination of shoring tower support piles above the ground surface were also considered. The movement displayed in these various elements pointed toward likely locations of collapse initiation among the numerous shoring towers. This study of movement allowed for a focused investigation to establish probable cause of the collapse.

Low flows were simulated in an artificial stream to determine the refuge-use strategies of two benthic New Zealand fish species, Canterbury galaxias Galaxias vulgaris and upland bullies Gobiomorphus breviceps, and to investigate how refuge availability and the rate of flow recession affect the type and incidence of refuge use. When riffles dewatered, upland bullies tended to move to runs, whereas Canterbury galaxias showed a stronger propensity to burrow into the substratum. Both species showed a strong and consistent tendency to move upstream when emigrating from riffles. Burrowing was more frequent on coarse substrata and during rapid flow recessions. The incidence of surface stranding increased with the rate of flow recession, but only when interstitial refugia were unavailable, and was higher on gravel than on cobble substrata. The effect of rate of flow recession and substratum size on the probability of stranding depended upon the type of refuge-use strategy adopted by the fishes. Rate of flow recession affected upland bullies more than Canterbury galaxias, whereas substratum size affected Canterbury galaxias more than upland bullies. These results suggest that the impact of disturbance is contingent upon species-specific refuge-use strategies, which result from interplay between refuge availability, the nature of the disturbance and species' behaviours and morphologies. When component species adopt contrasting refuge-use strategies, disturbance events may not consistently favour one species over another but rather inflict species-specific mortality that varies both temporally and spatially.

Of the 169 United States Army soldiers who deployed on a field training exercise to a remote area of Botswana for two weeks in January 1992, more than 30% developed a febrile illness within five days of their return. A diagnosis of South African tick typhus was suggested by soldiers' exposure to ticks, as well as the presence of eschars and vesicles at the site of tick bites, and tender regional lymphadenopathies. This high attack rate, experienced during such a short exposure period, emphasizes the hazard of illness due to Rickettsia conorii to persons visiting endemic areas. A rapid, diagnostic, semiquantitative enzyme immunoassay (DS) for detection of IgG and IgM antibodies to R. conorii was performed on 209 acute and convalescent sera from soldiers in the outbreak and on 75 control sera. For the acute sera from soldiers meeting the probable case definition of having both regional lymphadenopathy and tick bite eschar, as judged by an IgG indirect fluorescent antibody (IFA) test, the resulting sensitivity and specificity of the DS test were 100% and 48%, respectively. In the analysis of the acute sera, the DS test identified as reactive more of the probable cases (62%) than either the IgG (16%) or IgM (55%) IFAs. This simple and rapid diagnostic test could be useful in establishing a preliminary diagnosis of R. conorii rickettsiosis in remote settings when immediate confirmation by IFA is impossible.

Diminishing the activity of the renin-angiotensin system (RAS) plays a pivotal role in the treatment of heart failure. In addition to angiotensin converting enzyme (ACE) inhibitors and angiotensin-receptor blockers, direct renin inhibition has emerged as a potential adjunctive treatment to conventional RAS blockade. We sought to determine the effectiveness of this strategy after myocardial infarction (MI) in the setting of preexisting hypertension, a common premorbid condition in patients with ischemic heart disease.Ten-week-old female heterozygous hypertensive (mRen-2)27 transgenic rats (Ren-2), were randomized to one of five groups (n = 8 per group); sham, MI, MI + aliskiren, MI + lisinopril and MI + combination lisinopril and aliskiren. Cardiac function was assessed by echocardiography and in vivo cardiac catheterization. Untreated MI animals developed heart failure with hypotension, dilation, reduced ejection fraction (EF), and raised left ventricular end-diastolic pressure (LVEDP). Treatment with single agent treatment had only modest effect on cardiac function though combination therapy was associated with significant improvements in EF and LVEDP when compared to untreated MI animals (P0.05). Histologic analysis demonstrated increase extracellular matrix deposition and cardiomyocyte hypertrophy in the noninfarct region of all MI groups when compared with sham operated animals (P0.05) that was reduced by ACE inhibitor monotherapy and combination treatment but not by aliskiren alone.In a hypertensive rat model that underwent experimental MI, EF, and LVEDP, key functional indices of heart failure, were improved by treatment with combination ACE and direct renin inhibition when compared with either agent used alone.

Until recently, the culture of Helicobacter pylori in vitro has only been achievable with complex undefined media supplemented with blood products, such as Brain-heart infusion (BHI) medium, blood agar, chocolate agar, or lysed blood agar (1). Substrate utilization and metabolic activity during growth on these media is difficult to define; this has led to the use of techniques such as nuclear magnetic resonance (NMR) spectroscopy to investigate the metabolic pathways active in H. pylori (e.g., refs. 2-5). Defined media for the growth of H. pylori have now been described (6,7), however, and may facilitate future metabolic studies in this organism by more conventional techniques.

Exfoliation of aluminum-lithium (Al-Li) alloy 8090 (UNS A98091) in plate and sheet form was studied by measuring the compressive forces generated by voluminous grain boundary corrosion products. The forces were shown to be related closely to grain shape, with more elongated microstructures generating higher forces. Aging treatment of the alloy also was a factor. Corrosion product forces were ranked in the order: under-aged > over-aged > peak-aged. High susceptibility of the over-aged temper in 8090 differed from that of conventional, precipitation-hardened Al alloys and was attributed to the formation of anodic phases in the Li-containing material. Stress corrosion tests were performed on the plate using double-cantilever beam specimens. The sheet was tested under constant load in the through-thickness direction. KISCC values, the limiting values of stress intensity for stress corrosion to occur, were compared with the maximum corrosion product forces and supported the proposition that exfoliatio...

A 66-year old man presented with antero-lateral STEMI. An ulcerated plaque and thrombus were seen in the proximal LAD. We were unable to pass a thrombectomy catheter down the LAD. To avoid embolisation of debris a Spider FX distal protection device was placed into the circumflex artery. Following stent implantation the patient developed chest pain with inferolateral ST depression. Thrombus was extracted from the circumflex artery within the distal protection device. Noninfract related artery distal protection during primary PCI may be an appropriate safeguard where thrombectomy is not possible in an infarct-related left coronary branch.

Hydrogen peroxide has been used for decades as an effervescent haemostatic agent in arthroplasty. Recently it has been shown to adversely affect the material properties of PMMA. We aim to assess whether any such deleterious effects are demonstrated in an experimental model which mimics the clinical use of hydrogen peroxide. Matched pairs of cancellous bone samples were treated with a swab soaked in either saline or a 3% solution of hydrogen peroxide, prior to manufacture of cement-bone constructs using Palacos or Simplex cement. Thirty pairs were then compared by subjecting them to a torsional shear force until failure and a further thirty pairs were tested to failure in tension. There was no significant difference between the mean torques to failure for the Palacos-peroxide group versus the Palacos-saline group, or the Simplex-peroxide versus the Simplex-saline group (p=0.31 and 0.71 respectively). Similarly there was no significant difference between the mean tension loads to failure for the Palacos-peroxide group versus the Palacos-saline group, and the Simplex-peroxide versus the Simplex-saline group (p=0.79 and 0.23 respectively). We conclude that the use of hydrogen peroxide as an effervescent haemostatic agent has no detrimental effect on the mechanical integrity of the bone-cement interface when compared to normal saline.

A previously well 47-year-old woman presented with a 4-week history of non-productive cough and lethargy without weight loss, orthopnoea or exertional dyspnoea. She was normotensive and a non-smoker. Clinical examination was unremarkable, and no lymphadenopathy was detected. Routine blood tests including inflammatory markers were normal. The electrocardiogram showed sinus rhythm with non-specific T …

The finding that the systemic renin-angiotensin system (RAS) is not activated in most types of chronic renal disease has led to the suggestion that a local, intrarenal RAS may be an important determinant in the relentless progression of renal disease. Therefore, cell specific changes in various components of the RAS in response to renal mass reduction and angiotensin converting enzyme (ACE) inhibition were examined. Thirty Sprague-Dawley rats were randomly assigned to sham surgery, subtotal nephrectomy (STNx) alone or STNx treated with the ACE inhibitor, perindopril, and sacrificed after 12 weeks. In sham rats, renin mRNA and protein were only present in the juxtaglomerular apparatus. In contrast, in STNx kidneys, renin and angiotensin II expression were noted predominantly in renal tubular epithelial cells in association with overexpression of the prosclerotic cytokine, transforming growth factor-beta1 (TGF-beta1). In perindopril-treated STNx rats expression of renin and TGF-beta1 were similar to control animals. These finding indicate that following renal mass reduction there is pathological tubular expression of various components of the RAS. Furthermore, in contrast to the juxtaglomerular apparatus, tubular renin expression was reduced with ACE inhibition. These changes within the intrarenal RAS may be pathogenetically linked to the development of tubulointerstitial injury.

Helicobacter pylori is a spiral Gram-negative microaerophilic bacterium that causes one of the most common infections in humans; approximately 30-50% of individuals in Western Europe are infected and the figure is nearly 100% in the developing world. It is recognized as the major aetiological factor in chronic active type B gastritis, and gastric and duodenal ulceration and as a risk factor for gastric cancer. H. pylori normally inhabits the mucus-lined surface of the antrum of the human stomach where it induces a mild inflammation, but its presence is otherwise usually asymptomatic. A variety of virulence factors appear to play a role in pathogenesis. These include the vacuolating cytotoxin VacA, cytotoxin-associated proteins, urease and motility. All are under intense study in an attempt to understand how the bacterium colonizes and persists in the gastric mucosa, and how H. pylori infections lead to the disease state. Although an explosion of research on H. pylori has occurred within the past 15 years, most efforts have been directed at aspects of the bacterium and disease process which are of direct clinical relevance. Consequently, our knowledge of many aspects of the physiology and metabolism of H. pylori is relatively poor. This should change rapidly now that the complete genome sequence of a pathogenic strain has been determined. This review focuses attention on these more fundamental areas of Helicobacter biology. Analysis of the genome sequence and some detailed metabolic studies have revealed solute transport systems, an incomplete citric acid cycle and several incomplete biosynthetic pathways, which largely explain the complex nutritional requirements of H. pylori. The microaerophilic nature of the bacterium is of particular interest and may be due in part to the involvement of oxygen-sensitive enzymes in central metabolic pathways. However, the biochemical basis for the requirement for CO2 has not been completely explained and a major surprise is the apparent lack of anaplerotic carboxylation enzymes. Although genes for glycolytic enzymes are present, physiological studies indicate that the Entner-Doudoroff and pentose phosphate pathways are more active. The respiratory chain is remarkably simple, apparently with a single terminal oxidase and fumarate reductase as the only reductase for anaerobic respiration. NADPH appears to be the preferred electron donor in vivo, rather than NADH as in most other bacteria. H. pylori is not an acidophile, and must possess mechanisms to survive stomach acid. Many studies have been carried out on the role of the urease in acid tolerance but mechanisms to maintain the protonmotive force at low external pH values may also be important, although poorly understood at present. In terms of the regulation of gene expression, there are few regulatory and DNA binding proteins in H. pylori, especially the two-component 'sensor-regulator' systems, which indicates a minimal degree of environmentally responsive gene expression.

A pregnant patient at 38 weeks' gestation developed symptoms of local anaesthetic toxicity following intravenous regional anaesthesia (IVRA) for hand surgery, using a standard dose of lignocaine. Reports suggest that a number of factors, both physiological and pharmacological, combine to increase the likelihood of local anaesthetic (LA) toxicity in pregnancy despite employment of a conventional "safe" IVRA technique. It is suggested that for IVRA, pregnant patients are premedicated with a benzodiazepine, the tourniquet time is increased and the concentration of LA is decreased to reduce the risks of LA toxicity.

We compared a commercially available dot-blot immunoassay system with the indirect immunofluorescence assay (IFA) in tests of known negative and known positive sera from scrub typhus cases. Using a panel of 100 sera from patients with various rickettsial and nonrickettsial infections, we observed that the IFA was 99% specific and the dipstick assay was 98% specific. In tests of 91 sera (30 negative and 61 positive for scrub typhus antibodies) from a study of febrile patients in Malaysia, using the standard of an IFA titer1:64 as negative, an IFA titer1:128 as positive, and an IFA titer = 1:64 as either positive or negative (supported by clinical records), dipsticks were 83% specific and 90% sensitive. The quantitative correlation of the dipsticks to IFA titers was confirmed by significant differences in geometric means of inverse IFA titers corresponding to the number of positive dipstick spots (no dots = 8.5, one dot = 43.3, two dots = 206.7, and three dots = 676.9). The assay would enable physicians and public health workers who deal with patients to quickly diagnose and appropriately treat most cases of the disease, especially in areas of high prevalence where the proportion of false-positive results to true-positive results would be low.

The kinetics of ligand binding to the periplasmic C4-dicarboxylate binding protein (DctP) from Rhodobacter capsulatus were investigated by exploiting the changes in the intrinsic fluorescence of the protein upon binding ligands. Steady state measurements have shown that L-malate, succinate, and fumarate are all bound with sub-micromolar Kd values, whereas D-malate is bound 2 orders of magnitude more weakly. Stopped-flow studies have revealed that the binding process involves at least three steps. In the absence of ligand, the protein is in equilibrium between an essentially nonbinding form, BP1, and the binding form, BP2. Ligands bind to the BP2 form, shifting the equilibrium toward the BP2-L conformation, and also inducing a further isomerization of the protein, to the BP3-L form. The kinetic properties of the four different conformational states of the DctP protein identified in this study would be consistent with their identification as the closed-conformation, the open-conformation, an open-liganded conformation, and a closed-liganded conformation. The latter three states have been identified by x-ray crystallographic studies of binding proteins, but no kinetic or structural data have been presented previously to support the possibility of a closed but unliganded conformation.

Transposon mutagenesis was used to isolate insertion mutants of the photosynthetic bacterium Rhodobacter capsulatus which were unable to grow under aerobic conditions in the dark on malate, succinate or fumarate as sole carbon sources. Of five mutants isolated, all were deficient in C4-dicarboxylate transport. However, these mutants were still capable of photoheterotrophic growth, although at a slower rate than the wild type, on malate and succinate (but not fumarate). The mutated locus (designated dct) was complemented in trans using a cosmid gene bank. Subcloning and complementation analysis indicated that at least three closely linked genes essential for aerobic dicarboxylate transport were contained within an 8.3 kb region of the Rhodobacter capsulatus chromosome.

Tillage experiments in the South Australian mallee, over 8 years (1990–97), have demonstrated that cultivation directly below the seed at sowing controls rhizoctonia bare patch as effectively as 1 or 2 cultivations prior to sowing. When combined with a short chemical fallow and the use of press-wheels, this modified direct drilling technique can yield as well as, or better than, conventional farming systems. The combination of modified direct drilling and deep-banded urea increases the control of the disease in the first 2 weeks after the break in the season. In the first 2 weeks after the break, deep banding urea at sowing is more likely to increase yield, than modified direct drilling with urea broadcast at tillering, when both treatments are compared with standard direct drilling. In a reduced tillage system, a cultivation 6–11 days after the break in the season may be more effective in reducing bare patch than a cultivation at other times after the break.

1) Rhodobacter capsulatus (formerly Rhodopseudomonas capsulata) strain 37b4 was subjected to transposon Tn5 mutagenesis. 2) Kanamycin-resistant transconjugants were screened for their inability to reduce trimethylamine-N-oxide (TMAO) as judged by the lack of alkali production during anaerobic growth on plates containing glucose as carbon source and cresol red as pH indicator. 3) Of 6 mutants examined, all were found to have considerably decreased levels of methylviologen-dependent TMAO reductase activity and dimethylsulphoxide (DMSO) reductase activity. 4) Periplasmic fractions of one of these mutants (DK9) and of the parent strain were subjected to sodium dodecylsulphate polyacrylamide gel electrophoresis. The gels were stained for TMAO-reductase and DMSO-reductase. With the wild-type strain, only a single polypeptide band, Mr=46,000, stained for TMAO and DMSO reductase activity. In mutant DK9 this band was not detectable. 5) In contrast to the parent strain, harvested washed cells of mutant DK9 were unable to generate a cytoplasmic membrane potential in the presence of TMAO or DMSO under dark anaerobic conditions. 6) In contrast to the parent strain, DK9 was unable to grow in dark anaerobic culture with fructose as the carbon source and TMAO as oxidant.

The effects of various electron transport inhibitors upon the rates of reduction NO3-, dimethyl sulphoxide (DMSO) and N2O in anaerobic suspensions of Rhodobacter capsulatus have been studied. A new method for the determination of the rates of reduction of these auxiliary oxidants in intact cells is presented, based on the proportionality observed between the concentration of oxidant and the duration of the electrochromic carotenoid bandshift. For NO3-and N2O good agreement was found between rates of reduction determined using electrodes and those determined by the electrochromic method.

Summary: Pigment-protein complexes from Rhodomicrobium vannielii were prepared by detergent solubilization of intra-cytoplasmic membranes followed by gel electrophoresis or sucrose gradient centrifugation. These procedures gave rise to two native pigmented complexes. The major one (designated B800-865) was associated with two polypeptides of Mr 11000 and 13000 and was identified with the ‘accessory’ light-harvesting complex II found in other members of the Rhodospirillaceae. The minor complex (designated B885-RC) contained both reaction centre and light-harvesting bacteriochlorophyll. Detergent fractionation and reversible chemical cross-linking, followed by two-dimensional polyacrylamide gel electrophoresis, indicated a specific relationship between a membrane-bound cytochrome c-553 and the Mr 31000 subunit of the reaction centre.

Classification of remote sensing image data requires the multispectral domain to be segmented into distinct regions called spectral classes. These are related to the geometric character of the classifier and consequently have multidimensional spectral shapes that are different for parallelepiped, minimum distance and maximum likelihood classification. This is particularly significant for regions of multispectral space that are substantially continua with few discernible density maxima, as is frequently the case in practice.

The effect of sublethal gamma radiation on inbred mice chronically infected with scrub typhus rickettsiae was examined. Inbred mice which were inoculated with the Gilliam or Karp strain of Rickettsia tsutsugamushi by the subcutaneous route harbored the infection for at least 1 year. Irradiation of these animals at 12 or 52 weeks postinoculation with normally sublethal levels induced a significantly higher percentage of rickettsemic mice (recrudescence) than was seen in the unirradiated, similarly infected control animals. In addition, sublethal irradiation at 12 weeks induced a quantitative increase in total rickettsiae. Homologous antibody titers to the rickettsiae were examined for 5 weeks after irradiation to determine the role of the humoral response in radiation-induced recrudescence. Unirradiated, infected mice showed consistent titers of about 320 throughout the 5-week observation period, and the titer was not affected by exposure of up to 500 rads of gamma radiation. Drug dose-dependent radioprotection and modification of recrudescence was noted in infected, irradiated mice treated with the antiradiation compound S-2-(3-aminopropylamino)ethyl phosphorothioic acid. The results of this investigation supported the conclusion that the recrudescence of a chronic rickettsial infection in the appropriate host after immunological impairment due to gamma radiation can result in an acute, possibly lethal rickettsemia.

That there is no standing still is a fundamental principle in all that pertains to life; there must be either growth or decline. So with our schools and our teachers; they are either getting better and better or the reverse. A school system, to possess vitality, must recognize this fact and govern itself accordingly. This can best be done by making provision for aiding or training teachers while they are at work so that each teacher in the system may be offered such help and encouragement as to enable her to be a better teacher. In other words, one of the essential responsibilities of a successful school system is to use itself as a training institution whereby, from day to day and from year to year, each member of the staff may be acquiring greater professional skill. There are two groups or classes of teachers to be considered, the beginners and the experienced. The novice comes out of the normal school or the college far from a finished product. She usually knows at least something of the subject-matter she is expected to teach and has a speaking acquaintance with the method, though this is largely theoretical. She does not understand, or so it appears, some of the simplest rudiments of school management or classroom technique. Her best teaching qualification is her enthusiasm, which, if coupled with too much self -assurance, may become more of a liability than an asset. To give such a teacher an assignment and leave her to work out her own salvation approaches the criminal. There is bound to be too much suffering on her part besides a weakening of the whole organization. It may also mean a serious loss to the profession should the attendant discouragement cause a change of vocation. The weakness of the beginner may well be accepted as the inevitable

In appearing before this assembly I feel somewhat like an impostor, for I am not a mathematics teacher nor have I ever been one. Neither do I make any claim as a mathematician but am merely a plain superintendent of schools, somewhat young in experience and a trifle old-fashioned in ideas. As such I speak this afternoon and should you disagree with anything that is said you are at liberty to do so for “my hat is not in the ring” nor have I any fears of “recall.”

The rate of fungous deterioration was determined for 292 balsam fir (Abies balsamea (L.) Mill.) killed by the spruce budworm (Choristoneura fumiferana (Clem.) in an area of heavy tree mortality in northern New Brunswick. Trees dead less than one year and up to seven years were examined. Fifty fir trees dead 0 to 2 years in a light mortality area were also examined. Trees in the heavy mortality area deteriorated much more slowly than those examined by other workers in Ontario. Stereum chailletii (Pers.) Fr. and S. sanguinolentum (Alb. & Schw. ex Fr.) Fr. caused most of the incipient and advanced decay in New Brunswick, whereas S. chailletii caused all the incipient decay in trees dead less than one year in Ontario but was replaced after one year by Polyporus abietinus Dicks, ex Fr. which then caused most of the advanced decay. Advanced decay progressed faster in trees in the light mortality area in New Brunswick than in trees in the heavy mortality area. Nineteen species of basidiomycetes were associated with sapwood decay. Comments concerning the position and frequency of fungous occurrence in the different parts of the tree in relation to the number of years since death are made for eight of the more commonly isolated fungi. The introduction of S. chailletii into living trees by woodwasps and the differences observed in the development of P. abietinus in dead trees in the two regions are discussed.

Chloroflexus aurantiacus is a photosynthetic member of a group of microbes which represent an extremely deep branching in the eubacterial line of descent (Gibson et al., 1985; Oyaizu et al., 1987). The other genera in this grouping, the green nonsulphur bacteria, are Herpetosiphon and Thermomicrobium, with which Chloroflexus shares little apparent phenotypic resemblance. Rlthough Chloroflexus contains BChl a and c, the latter localized in chlorosomes attached to the cytoplasmic membrane, 16S rRNA sequencing studies have shown no phylogenetic relatedness to the green sulphur bacteria (Gibson et al., 1985). Indeed, in terms of reaction centre photochemistry (Blankenship et al., 1983), some aspects of electron transport (Bruce et al., 1982) and the wide range of carbon sources utilized for photoheterotrophic or chemoheterotrophic growth (Madigan et al. f 1974), the metabolism of Chloroflexus most resembles that of the purple nonsulphur bacteria. Unlike the Rhodospirillaceae, however, the Calvin cycle is apparently not used to fix CO2 into cell material under autotrophic growth conditions (Holo and Sirevag, 1986) and a novel mechanism has been postulated. In addition, the thermophilic character of Chloroflexus (optimum growth at 55°C) is seemingly rare amongst phototrophic bacteria.

The inherent cellular asymmetry in the cell cycles of the prosthecate budding bacteria, which involves the production of structurally and functionally distinct cell types, stems from the obligate polar growth patterns of these microbes. The examination of a range of bacteria, however, suggests that such asymmetry may be more widespread than hitherto recognized.

A seroepidemiological survey of 837 people and 383 febrile patients was performed in rural areas of Sabah. We determined that the rickettsial diseases scrub typhus and endemic typhus were uncommon causes of febrile illness, as was tick typhus, except in forest dwelling peoples. The rate of occurrence of SFGR specific antibody was 16.5% among 412 forest dwellers, indicating that tick typhus may be a frequent cause of illness in this population.

Antibodies to Rickettsia rickettsii were detected by indirect immunofluorescence in sera from 149 of 467 dogs (32%) examined from 4 military installations located in Kentucky, North Carolina, Pennsylvania, and Virginia. The prevalence at individual installations ranged from 4.3% at Fort Knox, Ky, to 63.4% at Fort Bragg, NC. Most of the seropositive dogs were in the working and sporting groups of dogs. The difference in antibody prevalence between sexes was not significant. Serologic responses were related to R rickettsii infection, although antibodies to R montana also were detected in a few of the sera. Comparison of serodiagnostic methods indicated that the indirect fluorescent antibody test was more sensitive than was the indirect hemagglutination test for obtaining survey data on the prevalence of Rocky Mountain spotted fever in the area.

Baeyer-Villiger Oxidation des Cyclododecanons (I) mit aus ?zOg/Maleinsaureanhydrid (II) erzeugter Permaleinsaure und Hydrolyse des Lactons (III) fuhrt zur w-Hydroxycarbonsaure (IV).

The authors of this article describe their successful experience, not only with the merging of two hospital laboratories, but with marketing their services to the offices of physicians on their medical staffs.