bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic relationships among isolates of Colletotrichum gloeosporioides from Stylosanthes spp. in Africa and Australia using RAPD and ribosomal DNA markers
Authors: Munaut F. , Hamaide N. , Vander Stappen J. , Maraite H.
Published: July 2002

Thirty‐three isolates of Colletotrichum gloeosporioides from various Stylosanthes species collected in Africa and Australia and associated with restricted (type A), extensive (type B) or nontypical anthracnose lesions (type C) were first compared by random amplified polymorphic DNA (RAPD) analysis. A phylogenetic tree was constructed based on 118 reproducible polymorphic bands generated with 16 random primers, using the upgma method. Twenty‐nine isolates were grouped in two main clusters, corresponding to types A and B, within which polymorphic subgroups were partially related to geographical origin. Strong similarities were observed among isolates of distant origin. Four isolates presented profiles completely different from the A and B types and were grouped in two additional clusters. To assess the phylogenetic relationship among isolates of various types and origins at the species level, the lnternal Transcribed Spacer region (ITS 1) of the ribosomal DNA was sequenced. Type A isolates and a restricted number of type B isolates selected in the RAPD clusters showed an homology of 99.4–100%. When compared with published sequence data, the isolates that were clustered separately in the phylogenetic tree, had the exact sequence of a C. gloeosporioides strain associated with the rotting of coffee berries, or of C. kahawae, the causal agent of coffee berry disease.
Human γδT Cells that Inhibit the In Vitro Growth of the Asexual Blood Stages of the Plasmodium falciparum Parasite Express Cytolytic and Proinflammatory Molecules
Authors: Troye-Blomberg M. , Worku S. , Tangteerawatana P. , Jamshaid R. , Söderström K. , Elghazali G. , Moretta L. , Hammarström M.-L. , Mincheva-Nilsson L.
Published: July 2002

The functional properties, regarding parasite growth inhibition in vitro, the cytotoxic potential and cytokine profiles of human γδ+ and αβ+ T cells, T‐cell lines and clones stimulated with Plasmodium falciparum‐antigen‐or T‐cell mitogen in vitro were investigated. Using reverse transcriptase‐polymerase chain reaction (RT‐PCR) and specific primers, mRNA for the cytolytic molecules perforin, granzyme A and B, Fas and Fas ligand (FasL) were detected in both the γδ‐ and the αβT cells. Despite this fact, only γδT cells inhibited, both Vδ1+ and Vδ2+, the in vitro growth of the asexual blood stages in a dose dependent manner. The inhibition required cell‐to‐cell contact and was not observed until the second parasite replication implied that the likely γδT‐cell target was the extracellular merozoite or schizont. The failure of αβT cells to inhibit the growth of the parasite suggests requirement of additional cytolytic molecules/signals or different receptor specificities exhibited by the γδT cells. Both the γδ‐ and αβT cells expressed mRNA for a large number of cytokines. Interferon (IFN)‐γ, interleukin (IL) IL‐5, IL‐6, IL‐8, tumour necrosis factor alpha (TNFα), tumour necrosis factor beta (TNF‐β)/lymphotoxin (LT) and T‐cell growth factor beta‐1 (TGF‐β1) were observed in all activated clones tested. No IL‐3 was detected, while IL‐1β, IL‐2, IL‐4, IL‐10 and GM‐CSF were variably expressed. In conclusion, our data show that γδT cells in malaria nonimmune individuals inhibit the asexual blood stages of P. falciparum malaria, while similarly activated αβT cells do not. Thus, it is likely that the γδT cells could play a mandatory role in the elimination of parasites and/or the regulation of the early immune response to malaria infection.
Effects of genotype and genotype—environment interaction on deoxynivalenol accumulation and resistance to Fusarium head blight in rye, triticale, and wheat
Authors: Miedaner T. , Reinbrecht C. , Lauber U. , Schollenberger M. , Geiger H. H.
Published: July 2002

Fusarium culmorum is one of the most important Fusarium species causing head blight infections in wheat, rye, and triticale. It is known as a potent mycotoxin producer with deoxynivalenol (DON), 3‐acetyl deoxynivalenol (3‐ADON), and nivalenol (NIV) being the most prevalent toxins. In this study, the effect of winter cereal species, host genotype, and environment on DON accumulation and Fusarium head blight (FHB) was analysed by inoculating 12 rye, eight wheat, and six triticale genotypes of different resistance levels with a DON‐producing isolate at three locations in 2 years (six environments). Seven resistance traits were assessed, including head blight rating and relative plot yield. In addition, ergosterol, DON and 3‐ADON contents in the grain were determined. A growth‐chamber experiment with an artificially synchronized flowering date was also conducted with a subset of two rye, wheat and triticale genotypes. Although rye genotypes were, on average, affected by Fusarium infections much the same as wheat genotypes, wheat accumulated twice as much DON as rye. Triticale was least affected and the grain contained slightly more DON than rye. In the growth‐chamber experiment, wheat and rye again showed similar head blight ratings, but rye had a somewhat lower relative head weight and a DON content nine times lower than wheat (3.9 vs. 35.3 mg/kg). Triticale was least susceptible with a five times lower DON content than wheat. Significant (P = 0.01) genotypic variation for DON accumulation existed in wheat and rye. The differences between and within cereal species in the field experiments were highly influenced by environment for resistance traits and mycotoxin contents. Nevertheless, mean mycotoxin content of the grain could not be associated with general weather conditions in the individual environments. Strong genotype‐environment interactions were found for all cereal species. This was mainly due to three wheat varieties and one rye genotype being environmentally extremely unstable. The more resistant entries, however, showed a higher environmental stability of FHB resistance and tolerance to DON accumulation. Correlations between resistance traits and DON content were high in wheat (P = 0.01), with the most resistant varieties also accumulating less DON, but with variability in rye. In conclusion, the medium to large genotypic variation in wheat and rye offers good possibilities for reducing DON content in the grains by resistance selection. Large confounding effects caused by the environment will require multiple locations and/or years to evaluate FHB resistance and mycotoxin accumulation.
A rapid method of estimating catches of abundant fruit fly species (Diptera: Tephritidae) in modified Steiner traps
Authors: Raghu S , Hulsman K , Clarke AR , Drew Rai
Published: July 2002

Males of many fruit fly species (Diptera: Tephritidae) are responsive to lures and these are used in modified Steiner traps for the regular monitoring of populations of fruit flies. Unfortunately, male lures are so attractive to many species of fruit fly that even weekly collections can produce catches of many hundreds of flies from a single trap. To help facilitate the assessment of trap catches in cases such as this, we compared total fly counts from real trap catches with various manual and computer‐simulated subsamples of those catches. Based on computer simulations, subsamples of 75, 100 and 200 flies accurately reflected the frequency of different fruit fly species in the original trap catch (mean trap catch size = 617.42 ± 53.72 SD flies, n = 26 weekly trap catches). However, based on the Chi‐squared analysis, subsample sizes of less than 200 individuals run the risk of being statistically unreliable. Subsamples based on weight were found to be just as accurate as subsamples where flies were drawn individually from the parent sample and thus offer a rapid method of producing accurate subsamples. Rare species were not well represented at any of the three subsample sizes and if the object of a program is to record rare species, then subsampling is not recommended. Where abundant species are the focus of a trapping program, subsampling offers a statistically reliable and time saving approach for assessing trap‐catch.
Change in the ratio of free‐to‐total prostate‐specific antigen during progression of advanced prostate cancer
Authors: TANAKA MASASHI , MURAKAMI SHINO , SUZUKI NORIYUKI , SHIMAZAKI JUN
Published: July 2002

Background
: The ratio of free‐to‐total prostate‐specific antigen (PSA) is different in benign prostatic hyperplasia and in the early stage of prostate cancer. The present study was undertaken to examine the ratio of free‐to‐total PSA in the advanced stage of this cancer and its subsequent change during course of the disease.

Methods
: Free and total PSA were measured in sera collected from the following patients with benign and cancerous prostatic diseases: 47 cases of benign prostatic hypertrophy, nine in T1C with less than 10 ng/mL of total PSA, 11 in stage C, 16 in D2, 22 in remission under endocrine therapy, and 12 in relapse. In addition, PSA was measured sequentially in four other patients who were also in relapse.

Results
: The ratio of free‐to‐total PSA was similar in early and advanced stages of untreated prostate cancer and was lower than that in benign prostatic hyperplasia. The ratio increased to the level of benign prostatic hyperplasia during remission from stages C and D2 under endocrine therapy. There was no correlation with the intervals from the start of the therapy to examination. Following relapse, the ratio came down gradually to the level obtained in untreated prostate cancer.

Conclusion
: The ratio of free‐to‐total PSA was similar in all stages of untreated prostate cancer. Response and relapse to endocrine therapy were associated with increase and decrease in ratio, respectively.
Lipid lowering explains the insulin sensitivity enhancing effects of a thiazolidinedione, 5‐(4‐(2‐(2‐phenyl‐4‐oxazolyl)ethoxy)benzyl)‐2,4 thiazolidinedione*
Authors: Yakubu‐Madus F. E. , Stephens T. W. , Johnson W. T.
Published: July 2002

Aim: Insulin resistance is a characteristic feature of type 2 diabetes and obesity. The present study examined the effects of TZD300512, a thiazolidinedione, on glucose and lipid metabolism in the fatty Zucker rat (fa/fa), a rat model of insulin resistance.

Methods: TZD300512 was administered (2.0 mg/kg/day) in the diet for 1 week to chronically catheterized Zucker fa/fa rats. We measured triglyceride clearance rate and hepatic triglyceride output. We assessed baseline glucose metabolism, and insulin‐mediated glucose uptake. We also determined whether the insulin sensitivity enhancing effects of TZD300512 could be reversed by infusion of Intralipid.

Results: TZD300512 treatment markedly reduced fasting plasma triglyceride by 72% and non‐esterified free fatty acids by 46%. Moreover, treatment significantly enhanced plasma triglyceride clearance (AUC; 60.36 ± 11.50 v 131.44 ± 18.45 m
m/min), but hepatic triglyceride output was not altered. Drug treatment significantly reduced fasting plasma glucose by 25%, plasma insulin by 73%, and had no effect on glucagon levels. Glucose infusion rate (GIR) needed to maintain euglycemia during hyperinsulinemic clamp was significantly increased from 34.96 ± 3.94 μmol/kg/min to 123.80 ± 4.80 μmol/kg/min, while whole body glucose uptake was more than doubled (58.49 ± 2.86 control vs. 126.97 ± 3.8 treated μmol/kg/min). Insulin‐induced suppression of hepatic glucose production was nearly complete with treatment. Intralipid infusion reversed drug‐induced improvement in insulin sensitivity.

Conclusions: These results suggest that TZD300512‐favourable alterations in lipid metabolism have a significant impact on its effectiveness in enhancing insulin sensitivity in a severely insulin resistant rodent model of type 2 diabetes.
Acarbose treatment does not change the habitual diet of patients with Type 2 diabetes mellitus
Authors: Lindström J. , Tuomilehto J. , Spengler M. , Group For The Finnish Acarbose Study
Published: July 2002

Aims It has been speculated that acarbose treatment in patients with Type 2 diabetes mellitus might induce changes in diet as a result of its adverse gastrointestinal effects. The aim of this study was to determine whether poor metabolic control can be improved by acarbose, and whether this might be because the acarbose supplementation provokes changes in diet.

Methods Poorly controlled Type 2 diabetic patients treated with oral hypoglycaemic agents (OHA) were randomized into either acarbose (100 mg t.d.s.) or placebo treatment. The double‐blind treatment lasted for 24 weeks. Four‐day food diaries and blood samples for efficacy analysis were collected at 0, 4, 12, and 24 weeks. Thirty‐six acarbose and 39 placebo‐treated patients completed the trial and were included in the final analyses.

Results At 24 weeks the baseline adjusted means of fasting, 1 and 2‐h postprandial blood glucose values were 9.3 vs. 10.5 (P = 0.02), 11.6 vs. 14.5 (P < 0.001) and 11.0 vs. 13.7 mmol/l (P < 0.001) and HbA1 9.3% vs. 10.2% (P = 0.002) in the acarbose and placebo groups, respectively. No significant differences in nutrient intakes between groups were observed. The energy intake and energy proportion of fat and carbohydrates remained unchanged in both groups.

Conclusions Acarbose significantly improves metabolic control in Type 2 diabetic patients poorly controlled with oral hypoglycaemic agents. This effect seems not to be a result of concomitant involuntary dietary changes, since acarbose did not induce modifications in diet during the study.
Women with a history of gestational diabetes of European and South Asian origin are shorter than women with normal glucose tolerance in pregnancy
Authors: Kousta E. , Lawrence N. J. , Penny A. , Millauer B. A. , Robinson S. , Johnston D. G. , McCarthy M. I.
Published: July 2002

SUMMARY

Aims  It has been reported that short individuals are more likely to have abnormalities of glucose homeostasis. The aim of this study was to examine the relationship between adult height and gestational diabetes mellitus (GDM), taking into account possible artefactual or confounding explanations.

Methods  Three hundred and forty‐six women with previous GDM (169 European, 102 South Asian, 75 Afro‐Caribbean) and 470 control women with no previous history of GDM (282 European, 94 South Asian and 94 Afro‐Caribbean) were studied. Post‐partum glucose status and height were measured.

Results  European and South Asian women with previous GDM were shorter than control women from the same ethnic groups (European: (mean ± sd) 162.9 ± 6.1 vs. 165.3 ± 6.8 cm, P < 0.0001; South Asian: 155.2 ± 5.4 vs. 158.2 ± 6.3 cm, P = 0.003, adjusted for age). A similar, but non‐significant trend was observed among Afro‐Caribbean women (162.2 ± 6.2 vs. 163.7 ± 6.1 cm, P = 0.1). Similar, significant height differences were observed in Europeans and South Asians when analysis was restricted to those GDM women who had received insulin during pregnancy. There was no association between height and glucose tolerance post‐partum within the GDM group.

Conclusions  European and South Asian women with previous GDM are shorter than control women from the same ethnic groups. The data demonstrate that this is unlikely to be an artefact resulting from the use of an fixed 75 g load in women of differing sizes, and suggest that there are likely to be common pathophysiological mechanisms underlying GDM and the determination of final adult height.
Prenatal diagnosis of the two‐vessel cord: implications for patient counselling and obstetric management
Authors: Catanzarite V. A. , Hendricks S. K. , Maida C. , Westbrook C. , Cousins L. , Schrimmer D.
Published: July 2002

The study was designed to investigate the implications of the sonographic diagnosis of the two‐vessel umbilical cord for patient counselling and pregnancy management. Retrospective analysis was carried out of prenatal findings and pregnancy outcomes when a two‐vessel cord was diagnosed in utero. Eighty‐two fetuses each with a single umbilical artery were diagnosed by ultrasound. Ten were aneuploid, including nine with visible structural defects and one with early onset intrauterine growth retardation. Of the remaining 72, 31 had other anomalies diagnosed postnatally; 27 of these had structural defects detected on ultrasound examination. However, in nine of these 27 sonographically abnormal fetuses, one or more major structural defects were missed by ultrasound examination. Among the 45 chromosomally normal fetuses with no visible defects on scan, four had anomalies diagnosed after birth.

Among the chromosomally normal singletons, six of 22 with other anomalies seen on scan and seven of 38 with no other visible defects on scan had intrauterine growth retardation. Among chromosomally normal twins, one of two with other anomalies seen and two of five appearing otherwise normal had intrauterine growth retardation; one twin set was delivered at 23 weeks after the demise of both twins.

Karyo typing is recommended whenever a two‐ vessel cord is seen in association with symmetric intrauterine growth retardation or any other defect. The fetus diagnosed with a two‐vessel cord and any other anomaly by ultrasound often has additional structural defects not seen on scan. The fetus with an isolated two‐vessel cord on scan seldom has unrecognized major anomalies, but is at risk for intrauterine growth retardation. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology
Anion binding in bovine corneal stroma
Authors: Kerswell Douglas H. , Hodson Stuart A.
Published: July 2002

Purpose: The corneal stroma strives to take up water because of the osmotic gradient created by fixed negative charges within the stroma. This fixed negative charge is known to be partly due to glycosaminoglycans and thought to be partly due to bound Cl− ions in the stroma. This study investigates the presence of anion binding within bovine stroma.

Methods: Bovine corneas were isolated, de‐epithelialized and de‐endothelialized. The stromal uptake of NaCl, NaAcetate, NaThiocyanate and NaHCO3 solutions at various concentrations was observed using a digital balance. The dry weight of each cornea was noted. Stromal hydrations were calculated and analysed.

Results: As the bathing solution concentration increased, for all solutions there was a significant increase in the calculated fixed negative charge values obtained. At physiological concentration of NaCl (150 mM), the fixed negative charge was calculated to be 39.98 ± 1.05 mEq 1−1. For NaAcetate, NaThiocyanate and NaHCO3 at 150 mM the fixed negative charge was calculated to be 38.64 ± 0.51, 43.62 ± 0.51 and 41.98 ± 0.65 mEq 1−1 respectively (n = 10, ± SEM).

Conclusions: The degree of anion binding in bovine corneal stroma varies from anion to anion and is dependent on the external bathing solution concentration. At 150 mM, the binding series from this study is NaThiocyanate > NaHCO3 > NaCl > NaAcetate.
The measurement of sampling efficiency and equivalent noise levels in binocular and monocular viewing conditions
Authors: Pardhan Shahina , Rose David , Gilchrist Jim
Published: July 2002

The measurement of contrast sensitivity in the presence of external visual noise allows any change in the detectability of a signal to be attributed to a change in sampling efficiency, or equivalent noise level, or both. Sampling efficiency indicates the efficiency by which the visual system is able to utilize the available stimulus information. The equivalent noise level gives a measure of the random background noise within the visual system. The aim of the study is to investigate whether binocular summation is due to a change in sampling efficiency or equivalent noise. Contrast detection in noise functions were measured in ten young normal adults under binocular and monocular viewing conditions. Sampling efficiency and equivalent noise levels were computed from the data. Results showed that sampling efficiency increased and equivalent noise decreased under binocular viewing compared to monocular. The existing theories of binocular summation are discussed.
The low vision distance telescope‐‐how useful an aid?
Authors: Rubinstein Martin P. , Lowe John B.
Published: July 2002

It is axiomatic that success in the use of any low vision aid depends largely upon the user's qualities of adaptability and skill. Distance telescopic aids, in particular, produce images with characteristics that are especially demanding of these qualities. Although patients appear largely content to accept their distance telescopes, a survey of individual successes and failures has not been reported.

In the low vision service at University Hospital, Nottingham, 2695 patients were examined over a nine year period (January 1987–December 1995). Of these, 142 patients (5.3%) were supplied with distance telescopes. This sample consisted of 83 males and 59 females. The age range was between 9–91 years. A total of 9 patients had returned their telescopes because they no longer needed them.

The remaining 133 patients were mailed a pilot questionnaire, aimed at evaluating their use of the telescope. Respondents to this were mailed a second, more detailed questionnaire, designed to examine in greater detail the individual's use of the appliance, their satisfaction with its performance etc.

A total of 74/133 patients (56%) returned detailed questionnaires completed with quantifiable information.

Statistical analysis showed:

1. Patients who found the telescopes easiest to use tended to use them most frequently

2. Monocularity tended to become commoner with age

But, adaptability and skill did not appear significantly compromised by:

3. Increasing age

4. Monocularity/binocularity status.

Fuller details of the results of this survey will be given in the poster.
Design of the Prospective Randomized Study for the Treatment of Patients with Thrombotic Microangiopathy
Authors: Röthele Elvira , Krumme Bernd , for the Prodromi Study Group Lars Christian Rump
Published: July 2002

Abstract: In thrombotic microangiopathies hemolytic uremic syndrome and thrombocytopenic purpura, plasma exchange (PE) therapy using fresh frozen plasma is standard. In almost 20% of the patients, however, this approach is ineffective. This prospective, randomized study for the treatment of patients with thrombotic microangiopathies (PRODROMI) compares PE with fresh frozen plasma (A) and cryosupernatant (B). The participating centers were the University Clinics of Freiburg, Hamburg, Düsseldorf, Essen, Göttingen, Mannheim, Ulm, Jena, Tübingen, Würzburg, Kreiskrankenhaus Offenburg, Städt Klinikum Karlsruhe, and Horst‐Schmidt Kliniken in Wiesbaden, Germany. Patients (18 to 80 years) were diagnosed by the individual centers based on clinical and laboratory findings (thrombocyte/fragmentocyte count, hemoglobin, serum creatinine, haptoglobin and lactate dehydrogenase levels; negative Coombs—test is obligatory). HIV infection, bone marrow, or solid organ transplantation were exclusion criteria. After written consent, patients were randomized in the A or B group. All patients received 1.5 mg/kg methylprednisolone as a basic therapy. The first PE always was performed with fresh frozen plasma (50 ml/kg). A minimum of 5 and a maximum of 10 PEs were required. Thrombocyte count above 150,000/μl was considered to be a successful therapy. Treatment failure was defined as not responding to 10 PE with a thrombocyte count above 150,000/μl or a fall below this value within 30 days after stopping PE. Patients with clinical and laboratory signs of thrombotic microangiopathy occurring later than 30 days after having stopped PE were considered to have a relapse. Primary endpoints were survival, intensity of required PE sessions (duration, volume, and number), and relapse rate. Follow‐up of clinical outcome was 2 years; von Willebrand Factor (vWF), vWF‐cleaving‐protease activity, and Factor H were determined.
Potential of Rheopheresis for the Treatment of Acute Ischemic Stroke When Initiated Between 6 and 12 Hours
Authors: Rössler Annegret , Berrouschot Jörg , Barthel Henryk , Hesse Swen , Köster Johannes , Schneider Dietmar
Published: July 2002

Abstract: Improvement of hemorheology is one of the most important approaches in the treatment of acute ischemic stroke. We investigated the influence of extracorporal rheopheresis (ER) on cerebral blood flow in patients with acute ischemic stroke and evaluated its therapeutic effect. Thirty‐three patients (rheopheresis group, 17; control group, 16; mean age 64 ± 10 years) with acute ischemic stroke were included in our prospective randomized trial. The first treatment was started within 12 h after onset of symptoms, and treatment was repeated 3 times at an interval of 24 h. Hemorheological parameters were measured before and after each session. The cerebral blood flow was analyzed using 99mTc‐ECD‐SPECT. The functional and neurological outcomes were determined by follow‐up investigations after 3 months. The hemorheological parameters were significantly different between the rheopheresis group (18% decrease of plasma viscosity, 55% decrease of red blood cell aggregation) and the control group (no decrease of both parameters). The single photon emission computed tomography (SPECT) analysis showed early reperfusion in 35% of the patients treated with rheopheresis and in 37% of the control group (NS). There were no differences in the neurological outcomes between the 2 groups. Extracorporal rheopheresis is practicable and safe. It rapidly and consistently improved the hemorheological parameters. Although this did not impact on cerebral perfusion or clinical outcome in patients with acute ischemic stroke in this report, we propose that ER deserves to be further evaluated by initiating the first treatment within 6 h post‐insult.
Rapid Reduction of Platelet Numbers in Thrombocytosis
Authors: Liumbruno Giancarlo , Centoni Paolo Emilio , Ceretelli Silvia , Sodini Maria Laura
Published: July 2002

Abstract: Thrombocytosis has been reported during chemotherapy with gemcitabine (GEM). A 71‐year‐old male patient who developed asymptomatic thrombocytosis (1,749 × 103/μl), secondary to GEM chemotherapy for lung carcinoma, was submitted to therapeutic plateletpheresis (TP). We adapted the software of the productive dual‐needle plateletpheresis of our cell separator in order to reduce the procedure time and the plasma volume harvested. With 2 low‐volume TP in 24 h, we achieved a 55% global reduction of the platelet count. While there are no accepted indications for prophylactic plateletpheresis in asymptomatic patients and the measured count should not, by itself, determine whether platelet reduction is indicated, a drastic reduction of an extremely high platelet count, especially if obtained with a relatively short procedure, can be important to prevent acute severe sequelae.
Effect of Salt Stress on Carbon Metabolism and Bacteroid Respiration in Root Nodules of Common Bean (Phaseolus vulgaris L.)
Authors: Ferri A. , Lluch C. , Ocaña A.
Published: July 2002

Abstract: In the present work, we examined the effect of salinity on growth, N fixation and carbon metabolism in the nodule cytosol and bacteroids of Phaseolus vulgaris, and measured the O2 consumption by bacteroids incubated with or without the addition of exogenous respiratory substrates. The aim was to ascertain whether the compounds that accumulate under salt stress can increase bacteroid respiration and whether this capacity changes in response to salinity in root nodules of Phaseolus vulgaris. The plants were grown in a controlled environment chamber, and 50, 100 mM or no NaCl (control) was added to the nutrient solution. Two harvests were made, at the vegetative growth period and at the beginning of the reproductive period. The enzyme activities in the nodule cytosol were reduced by the salt treatments, while in the bacteroid cytosol the enzyme activities increased at high salt concentrations at the first harvest and for ADH in all treatments. The data presented here confirm that succinate and malate are the preferred substrates for bacteroid respiration in common bean, but these bacteroids may also utilize glucose, either in control or under saline conditions. The addition of proline or lactate to the incubation medium significantly raised oxygen consumption in the bacteroids isolated from plants treated with salt.
A Phosphopeptide Corresponding to the Cytosolic Stretch Connecting Transmembrane Segments 8 and 9 of the Plasma Membrane H+‐ATPase Binds 14‐3‐3 Proteins and Inhibits Fusicoccin‐Induced Activation of the H+‐ATPase
Authors: Marra M. , Olivari C. , Visconti Sabina , Albumi Cristina , Aducci Patrizia , De Michelis Maria Ida
Published: July 2002

Abstract: A putative consensus domain for binding of 14‐3‐3 proteins to the plasma membrane (PM) H+‐ATPase was identified in the highly‐conserved sequence RSR(p)SWSF [where (p)S is Ser776 of the maize isoform MHA2], localized in the cytosolic stretch connecting transmembrane segments 8 and 9. A 15 amino acid biotinylated phosphopeptide comprising this motif: i) bound a recombinant 14‐3‐3 protein, ii) inhibited fusicoccin‐induced stimulation of the PM H+‐ATPase activity both in PM isolated from germinating radish (Raphanus sativus L.) seedlings and in ER isolated from Saccharomyces cerevisiae expressing AHA1 (an isoform of Arabidopsis thaliana PM H+‐ATPase), and iii) inhibited fusicoccin binding to PM isolated from germinating radish seedlings. The corresponding non‐phosphorylated peptide was inactive in all the performed assays. Together, these results suggest that the cytosolic strand connecting transmembrane segments 8 and 9 of the PM H+‐ATPase is a 14‐3‐3 binding site which might cooperate with the C‐terminal domain of the'enzyme in generating a stable association between the H+‐ATPase and 14‐3‐3 protein.
Strong flux pinning centers in Y-Ba-Cu-O films prepared by chemical vapor deposition
Authors: Watanabe K. , Matsushita T. , Kobayashi N. , Kawabe H. , Aoyagi E. , Hiraga K. , Yamane H. , Kurosawa H. , Hirai T. , Muto Y.
Published: July 2002

The Y-Ba-Cu-O film prepared by chemical vapor deposition showed Tc=91.5 K and Bc2 (77.3 K)=60 T defined by zero resistance. The Jc values measured at 77.3 K were 7.8×105 A/cm2 at B=0 and 1.0×105 A/cm2 at 16 T, magnetic fields perpendicular to the c axis. Small disk-shaped precipitates possibly regarded as strong flux pinning centers in the Y-Ba-Cu-O films were observed using transmission electron microscopy. The evaluation of Jc related to the concentration and configuration of the precipitates was in reasonable agreement with the measured Jc values.
Solubility of interstitial oxygen in silicon
Authors: Wijaranakula W.
Published: July 2002

An indirect method of determining the solubility of interstitial oxygen in silicon by monitoring the precipitation rate of oxygen is presented. The solubility of interstitial oxygen is described by the Arrhenius equation Ceqi = 5.5 × 1020 exp(−0.89 eV/kT)atoms/cm3. The estimated solubility is in agreement with the published data obtained from the infrared measurements. The result indicates that the nucleation model in condensed systems proposed by Becker [Pro. Phys. Soc. 52, 71 (1940)] is also applicable to the precipitation kinetics of oxygen in silicon.
Absorption redshift in TiO2 ultrafine particles with surfacial dipole layer
Authors: Zhou Bingsuo , Xiao Liangzhi , Li Tie Jin , Zhao Jialong , Lai Zhuyou , Gu Shiwei
Published: July 2002

It is found that the TiO2 ultrafine particles (UFP) coated with a layer of stearic acid radicals had a significant red shift of their absorption band edge and clear photoluminescence at room temperature (RT), which are in contrast with that of bulk TiO2 and naked TiO2 UFP. It was concluded that these results are related to the self-trapped exciton absorption due to the interfacial dipole layer of stearic acid radicals on the TiO2 UFP surface.
Third-harmonic generation in GeO2-doped silica single-mode optical fibers
Authors: Nicácio D. L. , Gouveia E. A. , Borges N M. , Gouveia-Neto A. S.
Published: July 2002

Third-harmonic generation of 1.319 μm Nd:YAG laser pulses in circular-core GeO2-doped silica single-mode fibers is reported. The experimental results have shown that the blue-violet light generated at 439 nm is less than 0.2 nm wide and its intensity depends strongly upon GeO2-doping concentration for fixed fiber length and pump power. It has been observed that for GeO2-doping concentrations greater than 9 mol %, the third-harmonic signal was the unique visible wavelength line exiting the fiber span throughout the spectral region of 400–800 nm. The frequency tripling process started immediately with fiber pump light illumination, i.e., no previous long-time preparation mechanism was required in order to have appreciable third-harmonic generation.
Evidence for step flow growth of Bi-Sr-Ca-Cu-O thin films on vicinal substrates by metalorganic chemical vapor deposition
Authors: Sugimoto Tsunemi , Kubota Nobuhiko , Shiohara Yuh , Tanaka Shoji
Published: July 2002

Two-dimensional nuclei and the resulting two-dimensional islands as well as the steps were observed at the surface of the Bi-Sr-Ca-Cu-O thin films grown on the vicinal substrates misoriented by 1°, but only the steps were observed at the surface of the films grown on the vicinal substrates misoriented by 5°. The step distance of the films grown on the vicinal substrates misoriented by 1° was longer than those of the films grown on the vicinal substrates misoriented by 5°. The competition between the propagation of the surface steps and the formation of two-dimensional nuclei can be explained qualitatively by the relation between the step distance and the mean time for surface diffusion of the adsorbing species. These results experimentally indicate that the growth of Bi-Sr-Ca-Cu-O thin films on vicinal substrates have proceeded in the step flow mode.
Real-time elimination of dead time and afterpulsing in counting systems
Authors: Finn M. A. , Greenlees G. W. , Hodapp T. W. , Lewis D. A.
Published: July 2002

A data taking scheme is described in which two photomultipliers record photons from a light source. It is shown that if the chain of recorded events is chosen to alternate between the two detectors, first-order effects of dead time and afterpulsing present in the two individual detectors are eliminated. This alternating scheme results in the detection efficiency being halved.
Technique for measurement of resistivity versus simultaneous temperature and pressure in a tetrahedral anvil press
Authors: Schaefer M. W. , Webb A. W.
Published: July 2002

Electrical resistivity measurements of materials as a function of pressure and temperature simultaneously are valuable indicators of structural phase changes and of electronic properties. Such measurements are difficult, however, and relatively few materials have been studied in this way. A sample holder for a tetrahedral anvil apparatus has been modified so that such measurements may be made. The calibration of the Pt/Pt10Rh thermocouple used to determine the temperature of the sample was found to be affected by pressure, and preliminary recalibration of this thermocouple under pressure was performed. Reasonable agreement was found between the phase diagram of CdTe determined with the apparatus used in this study and that previously published.
Transformation of histograms
Authors: Falk W. R.
Published: July 2002

A method of transforming a histogram of one variable into a histogram of another variable is presented. No assumptions are made regarding the nature of either the initial or final distributions. The superiority of the method over simple linear interpolation is demonstrated.
A high-power, power-modulated TEA CO2 laser system as a driving source of electrostatic plasma waves
Authors: Sasaki Koichi , Takahashi Kouichi , Fujii Takaharu , Nagatsu Masaaki , Tsukishima Takashige
Published: July 2002

A high-power, power-modulated transversely excited atmosphere (TEA) CO2 laser system is developed with the intention of applying it to high-temperature plasmas for diagnostic purpose. Two-mode pulse injection locking is adopted to obtain the required output pulses of the TEA CO2 laser. Together with the power modulation, the gain-switched spike of the output pulses are also suppressed by the adopted method, resulting in pulse lengthening. Two feedback loops are incorporated for reliable power modulation. The power-modulated output so obtained is used to excite electrostatic plasma waves in laboratory plasmas.
Performances of large multilayer mirrors for the 0.5–1.5 nm range
Authors: Malek C. Khan , Moreno T. , Barchewitz R. , Rivoira R. , Lepêtre Y.
Published: July 2002

6-in.-diam multilayer mirrors were fabricated for a double mirror monochromator designed to select photon energies between 830 and 1240 eV (0.5–1.5 nm). Coatings with 50 and 40 Mo/C bilayers with a bilayer d spacing of 4.1 and 4.6 nm, respectively, and a division parameter of Γ=0.44, were deposited by the triode sputtering method on 6-in.-diam silicon with 5% d uniformity. Similar coatings were also deposited on 2 in. silicon wafers. Peak reflectivity and integrated reflectivities were measured at several wavelengths between 0.5 and 1.5 nm using monochromatized synchrotron radiation. Measurements were performed along a 4 in. diameter for the large area coatings. The resolving power as measured in the center of the six inch mirrors was found to be 41 and 46 at 826 and 1240 eV, respectively, which compares well with the corresponding theoretical values of 43 and 40. The performance of a matched pair of multilayer mirrors with the smaller areas in the double mirror configuration was experimentally investigated as well. Reflectivity values for the two mirror configuration scheme were calculated from the experimental data for the individual mirrors. Possible applications of such monochromator in lithography research are briefly described.
A new Fourier transform millimeter wave spectrometer
Authors: Schwarz R. , Guarnieri A. , Grabow J.-U. , Doose J.
Published: July 2002

We present the details of a new type of spectrometer which allows the recording of molecular emission signals in the microwave and millimeter wave region with subsequent Fourier transformation. First experiments up to 49 GHz have been carried out, but we claim that the biphase modulator used to 49 GHz will allow broadbanded spectroscopy up to the 100-GHz region.
Extraction of interface state density profile from the maximums of the parallel conductance versus applied gate bias curves G
p(Va), using the conductance technique
Authors: Papadas C. , Morfouli P. , Ghibaudo G. , Pananakakis G.
Published: July 2002

A fast method for extracting the interface trap density profile of the semiconductor-insulator interface in metal-insulator-semiconductor structures is proposed. The method is based on the well known conductance technique and extracts the interface state density profile from the maximums of the parallel conductance versus applied gate bias curves, Gp(Va). In addition, this method is directly applicable to fully automated experimental setups available in industrial environments.
Multiwavelength pyrometry: Radiance temperature versus wavelength curve should be used for temperature determination
Authors: Hoch Michael
Published: July 2002

In multiwavelength pyrometry it is very difficult to represent the wavelength variation of emissivity so that a ‘‘correct’’ blackbody temperature T0 is obtained. On the other hand, use of Tr’s, the radiance temperature, permits the calculation of the blackbody temperature T0. In all cases studied up to now, in the wavelength range 0.4–4 μm, we have a linear relationship between Tr and L, the wavelength, Tr = Tlin − hL, where Tlin is the calculated blackbody temperature.
Novel method for determining the Curie temperature of ferroelectric films
Authors: Kwok Chi Kong , Desu Seshu B.
Published: July 2002

A novel technique to measure the Curie temperature of ferroelectric thin films has been developed. The method is based on identifying changes in slope of film stress versus temperature plot. At the Curie temperature, ferroelectric films undergo a phase transition from ferroelectric phase to paraelectric phase. Due to this phase transformation, physical properties of films such as elastic constants and coefficients of thermal expansion also change at the Curie temperature. Consequently, at this temperature the temperature coefficient of film stress changes since it is related to elastic constants and thermal expansion coefficient. Thus, by measuring the film stress as a function of temperature, the Curie temperature can be determined. The Curie temperatures measured by this method are in good agreement with the literature values. Small discrepancies that were observed can be attributed to the intrinsic stresses present in the films.
Photon-assisted tunneling through a quantum dot at high microwave frequencies
Authors: Blick R. H. , Haug R. J. , van der Weide D. W. , von Klitzing K. , Eberl K.
Published: July 2002

We investigate the influence of high frequency microwave radiation on single electron tunneling through a quantum dot. Effective coupling of the radiation to the quantum dot is achieved by an on-chip integrated broadband antenna. Simulations of the current distribution on the antenna are shown. We find that radiation with a frequency of ν=155 GHz, which corresponds to half of the bare charging energy Ec/2 results in an additional conductance peak within the Coulomb blockade regime. This additional resonance is attributed to photon-assisted tunneling.
UHV-compatible electrostatically driven tuning fork chopper
Authors: Kebabian Paul L. , Kallelis Spiros , Nelson David D. , Freedman Andrew
Published: July 2002

We have developed an electrostatically driven tuning fork chopper which is compatible with an ultrahigh vacuum (UHV) environment. Constructed with a commercially available tuning fork using stainless steel and alumina parts, the chopper is capable of operating while exposed to high temperature samples and corrosive gases. Operation in an UHV environment while modulating both optical and molecular beams is demonstrated.
Search for possible radiation damage on a NdFeB permanent magnet structure after two years of operation
Authors: Pflüger J. , Heintze G. , Vasserman I.
Published: July 2002

Recently there has been some concern about possible radiation damage due to ionizing particles present in high energy storage rings such as multi-GeV electrons, fast neutrons, or hard photons. Partial demagnetization has been observed on undulators after mis-steering of the injected electron beam. Our interest was focused to possible radiation damage of a permanent magnet insertion device during routine operation of a storage ring. Therefore, we repeated the magnetic measurements on one of the three 4.0 m long x-ray wigglers used at place ♯2 in DORIS III. This device is in operation since 1991. The results were compared to the data taken before installation. The total dose was determined from measurements with thermoluminescence dosimeters and the known number of stored ampere hours. The results which show no significant degradation of the magnetic performance are presented and discussed.
Far-ultraviolet absolute reflectometer for optical constant determination of ultrahigh vacuum prepared thin films
Authors: Aznárez J. A. , Larruquert J. I. , Méndez J. A.
Published: July 2002

An absolute reflectometer is described, which can determine the optical constants of thin films prepared and maintained in ultrahigh vacuum (UHV) in the 30–200 nm far-ultraviolet (FUV) region. The optical constants are calculated with Fresnel equations from reflectance measurements as a function of the incidence angle, which can be continuously varied from near-normal to grazing incidence. Corrections for the surface roughness effects of both the deposited film and the substrate on the reflectance in the calculation of optical constants were incorporated. The surface roughness was determined by atomic force microscopy. An innovative feature of the instrument is an oxidation chamber containing an atomic oxygen source attached to the reflectometer. Inside this chamber the FUV reflectance degradation of materials, caused by oxidation processes in low earth orbits, can be simulated on freshly prepared UHV samples. Another improvement of the reflectometer is the capability of performing the reflectance measurements in two perpendicular incidence planes. The average of these measurements obviates the unknown of the polarization state of the light beam emerging from the monochromator. However, this averaging may become inexact in the presence of a lateral inversion error in the reflected beam caused by the lack of uniformity of the beam and the detector.

A modification in the calculation algorithm was introduced to reduce the influence of this error. The implementation of a differential pressure system in four stages and a specifically designed device for modulation and monitoring of the light beam has allowed the use of weak spectral lines and the continuum of helium from the emission of a windowless capillary discharge lamp. Some results of reflectance measurements on freshly prepared aluminum films and after exposure to controlled doses of atomic oxygen are presented.
Current-to-voltage converter for linearity correction of low shunt resistance photovoltaic detectors
Authors: Makai Janos P. , Makai Jozsef J.
Published: July 2002

The most accurate absolute calibration of radiometric transfer standard detectors is carried out by cryogenic radiometers at a usually high irradiance level. A radiometric scale can be maintained by these calibrated detectors in a given irradiance range if they are linear or their nonlinearity is predictable in this range. The linearity of photovoltaic quantum detectors can be affected among others by their shunt resistance and the applied circuitry. Many of the radiometric quality large-area photodiodes exhibit very low shunt resistance in comparison to Si detectors. When used with a traditional current-to-voltage converter the requirement of the ideal short-circuit operation is not always met. Consequently, part of the photoinduced current flows through the shunt resistance of the detector as a shunt current, and only the rest produces the output voltage. This shunt current is highly temperature dependent and is generally proportional to the output voltage causing a nonlinear deviation of the output signal if the feedback resistor of the current-to-voltage converter, i.e., the sensitivity is changed. To practically eliminate the shunt current the bootstrapping technique was applied to these detectors, it enhanced the linear range of sensitivity by more than two decades. The circuit theory and the noise sources are detailed.
Photothermal deflection spectroscopy of an aqueous sample in a narrow bore quartz capillary
Authors: Spear Jonathan D. , Klunder Gregory L. , Russo Richard E.
Published: July 2002

An apparatus to perform photothermal deflection spectroscopy on liquid samples within a cylindrical capillary is described. A tunable dye laser, modulated by an optical chopper, serves as an excitation source. The resolution of a spectral absorption peak near 575 nm, of a 1×10−3 M Nd3+ aqueous solution, demonstrates the effectiveness of the system. The sample is contained within a 75 μm internal diameter quartz capillary, typical of those used for capillary electrophoresis. Across the middle of the probed section of the capillary, the magnitude of the resolved peak is 5.2×10−5 absorbance units. A helium–neon laser, focused to a 1/e2 waist diameter of 40 μm, provides an optical probe beam across the center of the sample, overlapping the excitation beam at an angle of 3°. Maximum signal-to-noise ratio is achieved with the apparatus when the excitation beam is modulated at a frequency near 205 Hz. The deflection responsivity of the probe beam at this frequency is 650 nrad per μW of absorbed excitation radiation, with an internal noise level in the system of 0.6 nrad Hz−1/2. The shot noise from probe beam radiation upon the photodiodes in the position sensitive detector exceeds noise from other sources.