2,842 research outputs found
Finished Genome Sequences of Xanthomonas fragariae, the Cause of Bacterial Angular Leaf Spot of Strawberry.
Xanthomonas fragariae is a foliar pathogen of strawberry that is of significant concern to nursery production of strawberry transplants and field production of strawberry fruit. Long-read sequencing was employed to generate finished genomes for two isolates (each with one chromosome and two plasmids) from symptomatic plants in northern California
Inhibition of Xanthomonas fragariae, Causative Agent of Angular Leaf Spot of Strawberry, through Iron Deprivation.
In commercial production settings, few options exist to prevent or treat angular leaf spot (ALS) of strawberry, a disease of economic importance and caused by the bacterial pathogen Xanthomonas fragariae. In the process of isolating and identifying X. fragariae bacteria from symptomatic plants, we observed growth inhibition of X. fragariae by bacterial isolates from the same leaf macerates. Identified as species of Pseudomonas and Rhizobium, these isolates were confirmed to suppress growth of X. fragariae in agar overlay plates and in microtiter plate cultures, as did our reference strain Pseudomonas putida KT2440. Screening of a transposon mutant library of KT2440 revealed that disruption of the biosynthetic pathway for the siderophore pyoverdine resulted in complete loss of X. fragariae antagonism, suggesting iron competition as a mode of action. Antagonism could be replicated on plate and in culture by addition of purified pyoverdine or by addition of the chelating agents tannic acid and dipyridyl, while supplementing the medium with iron negated the inhibitory effects of pyoverdine, tannic acid and dipyridyl. When co-inoculated with tannic acid onto strawberry plants, X. fragariae's ability to cause foliar symptoms was greatly reduced, suggesting a possible opportunity for iron-based management of ALS. We discuss our findings in the context of 'nutritional immunity,' the idea that plant hosts restrict pathogen access to iron, either directly, or indirectly through their associated microbiota
Acetazolamide-mediated decrease in strong ion difference accounts for the correction of metabolic alkalosis in critically ill patients
INTRODUCTION: Metabolic alkalosis is a commonly encountered acid–base derangement in the intensive care unit. Treatment with the carbonic anhydrase inhibitor acetazolamide is indicated in selected cases. According to the quantitative approach described by Stewart, correction of serum pH due to carbonic anhydrase inhibition in the proximal tubule cannot be explained by excretion of bicarbonate. Using the Stewart approach, we studied the mechanism of action of acetazolamide in critically ill patients with a metabolic alkalosis. METHODS: Fifteen consecutive intensive care unit patients with metabolic alkalosis (pH ≥ 7.48 and HCO(3)(- )≥ 28 mmol/l) were treated with a single administration of 500 mg acetazolamide intravenously. Serum levels of strong ions, creatinine, lactate, weak acids, pH and partial carbon dioxide tension were measured at 0, 12, 24, 48 and 72 hours. The main strong ions in urine and pH were measured at 0, 3, 6, 12, 24, 48 and 72 hours. Strong ion difference (SID), strong ion gap, sodium–chloride effect, and the urinary SID were calculated. Data (mean ± standard error were analyzed by comparing baseline variables and time dependent changes by one way analysis of variance for repeated measures. RESULTS: After a single administration of acetazolamide, correction of serum pH (from 7.49 ± 0.01 to 7.46 ± 0.01; P = 0.001) was maximal at 24 hours and sustained during the period of observation. The parallel decrease in partial carbon dioxide tension was not significant (from 5.7 ± 0.2 to 5.3 ± 0.2 kPa; P = 0.08) and there was no significant change in total concentration of weak acids. Serum SID decreased significantly (from 41.5 ± 1.3 to 38.0 ± 1.0 mEq/l; P = 0.03) due to an increase in serum chloride (from 105 ± 1.2 to 110 ± 1.2 mmol/l; P < 0.0001). The decrease in serum SID was explained by a significant increase in the urinary excretion of sodium without chloride during the first 24 hours (increase in urinary SID: from 48.4 ± 15.1 to 85.3 ± 7.7; P = 0.02). CONCLUSION: A single dose of acetazolamide effectively corrects metabolic alkalosis in critically ill patients by decreasing the serum SID. This effect is completely explained by the increased renal excretion ratio of sodium to chloride, resulting in an increase in serum chloride
The development of the Meaning in Life Index (MILI) and its relationship with personality and religious behaviours and beliefs among UK undergraduate students
The scales available for assessing meaning in life appear to be confounded with several related constructs, including purpose in life, satisfaction with life, and goal-directed behaviour. The Meaning in Life Index (MILI), a new instrument devised as a specific measure of meaning in life, was developed from responses to a pool of 22 items rated by a sample of 501 undergraduate students in Wales. The nine-item scale demonstrated sufficient face validity, internal consistency, and scale reliability to commend the instrument for future use. With respect to personality, the MILI scores were most strongly predicted by neuroticism (negatively), and less strongly by extraversion (positively) and psychoticism (negatively). With respect to several religious behavioural variables, those who attended church at least weekly returned significantly higher MILI scores than those who attended church less frequently. Intrinsic religiosity was the only orientation to be significantly associated with the MILI scale scores, although the magnitude of the association was smaller than anticipated. These results suggest that meaning in life is associated more strongly with individual differences in personality than with specific religious behaviours and attitudes. The implications of these results are discussed in terms of individual's personal values and attitudes that might underlie their experience of a meaning in life
Hubungan di antara dimensi personaliti, Konsep Kendiri dan pengaruh keluarga ke atas pencapaian pelajar di Rancangan Skim Felda, Johor
The purpose of this study was to identify the relationship between the dimensions of personality, self-concept and family influence on students’ performance. The sample consists of 214 students from two secondary schools in the FELDA settlement in Johor. Random cluster sampling was employed to select participants for the study. A pilot test was conducted to assess the internal consistency of the questionnaire used in the study which was the Malay version of the Junior Eysenck Personality Inventory (JEPI) (α = .57), the Malay version of the Tennessee Self-concept Scale (α = .86) and the family influence questionnaire (α = .79). These instruments were used to examine the effects of family influence in the aspects of family cohesiveness, religious and moral aspect and freedom aspect. Pearson's Correlation was used to analyze the relationship between the dimensions of personality, self-concept and family influence. The results show a relationship between the dimensions of personality and self-concept, and between the dimensions of personality and family cohesiveness. However, there was no relationship between the dimensions of personality and the religious and moral and freedom aspect. The results also show that there was a strong relationship between self-concept and family cohesiveness and a moderate relationship between self-concept and the religious and moral aspect. However, there was no relationship between self-concept and freedom. The implications of the study were also discussed
Spontaneous emission of atomic systems in the presence of incident fields
We characterise the spontaneous emission time and direction from small
numbers of dipole-coupled two-level atoms (2LAs) in the presence of incident
fields. We show how to use adiabatic passage to admit population transfer
between states in the one-quantum subspace for two and three 2LAs. Our method
is a multi-atom generalisation of stimulated-Raman-adiabatic-passage (STIRAP)
for a single multi-level atom. We use numerical results to justify an ansatz
that enables us to give analytical expressions for the directional emission
which depends on the incident fields. Our results admit a characterisation of
the efficacy of population transfer in small numbers of dipole-coupled 2LAs,
and are applicable to proof-of-principle experiments involving dipole-coupled
2LAs.Comment: 10 pages, 6 figure
New physics explanations of in light of the FNAL muon measurement
The Fermilab Muon experiment recently reported its first measurement of
the anomalous magnetic moment , which is in full
agreement with the previous BNL measurement and pushes the world average
deviation from the Standard Model to a significance of
. Here we provide an extensive survey of its impact on beyond the
Standard Model physics. We use state-of-the-art calculations and a
sophisticated set of tools to make predictions for , dark matter and LHC
searches in a wide range of simple models with up to three new fields, that
represent some of the few ways that large can be explained. In
addition for the particularly well motivated Minimal Supersymmetric Standard
Model, we exhaustively cover the scenarios where large can be
explained while simultaneously satisfying all relevant data from other
experiments. Generally, the result can only be explained by
rather small masses and/or large couplings and enhanced chirality flips, which
can lead to conflicts with limits from LHC and dark matter experiments. Our
results show that the new measurement excludes a large number of models and
provides crucial constraints on others. Two-Higgs doublet and leptoquark models
provide viable explanations of only in specific versions and in
specific parameter ranges. Among all models with up to three fields, only
models with chirality enhancements can accommodate and dark matter
simultaneously. The MSSM can simultaneously explain and dark matter for
Bino-like LSP in several coannihilation regions. Allowing under abundance of
the dark matter relic density, the Higgsino- and particularly Wino-like LSP
scenarios become promising explanations of the result.Comment: 106 pages, 20 figures, 5 tables; v2 added references, minor
corrections to table 2 and improvements to Figs 2,3 and 4; v3 as published in
JHE
Chronic multifocal non-bacterial osteomyelitis in hypophosphatasia mimicking malignancy
BACKGROUND: Hypophosphatasia (HP) is characterized by a genetic defect in the tissue-nonspecific alkaline phosphatase (TNSALP) gene and predominantly an autosomal recessive trait. HP patients suffer from reduced bone mineralization. Biochemically, elevated concentrations of substrates of TNSALP, including pyridoxal-5'-phosphate and inorganic pyrophosphate occur in serum, tissues and urine. The latter has been associated with chronic inflammation and hyperprostaglandinism. CASE PRESENTATION: We report on 2 affected children presenting with multifocal inflammatory bone lesions mimicking malignancy: A 6 years old girl with short stature had been treated with human growth hormone since 6 months. Then she started to complain about a painful swelling of her left cheek. MRI suggested a malignant bone lesion. Bone biopsy, however, revealed chronic inflammation. A bone scan showed a second rib lesion. Since biopsy was sterile, the descriptive diagnosis of chronic non-bacterial osteomyelitis (CNO) was established. The diagnostic tests related to growth failure were repeated and subsequent analyses demonstrated a molecular defect in the TNSALP gene. The second girl (10 years old) complained about back pain after she had fallen from her bike. X rays of her spine revealed compressions of 2 thoracic vertebrae. At first these were considered trauma related, however a bone scan did show an additional lesion in the right 4(th )rib. A biopsy of this rib revealed a sterile lympho- plasmocytoid osteomyelitis suggesting multifocal CNO. Further analyses did show a decreased TNSALP in leukocytes and elevated pyridoxal phosphate in plasma, suggesting a heterozygous carrier status of HP. CONCLUSION: Chronic bone oedema in adult HP and chronic hyper-prostaglandinism in childhood HP do suggest that in some HP patients bone inflammation is present in conjunction with the metabolic defect. Sterile multifocal osteomyelitis could be demonstrated. Non-steroidal anti-inflammatory treatment achieved complete remission. These cases illustrate chronic inflammation of the bone as a new feature of HP
Follow-up for breast cancer - the patients' view
Background: International and national guidelines (S3 guideline) for the surveillance of post-treatment breast cancer patients recommend a clinical follow-up including routine history and physical examination and regular mammograms. The practice of a clinical follow-up has been often discussed, but has been proven not to be inferior when compared to an intensified follow-up in randomized trials. Patients and Methods: The present manuscript reports the patients' view on the basis of a survey including 2000 patients with a history of breast cancer. Results: A total of 452 patients (22.6%) answered the questionnaire. The median age was 62 years (range 23-85 years). More than 80% of the patients were disease-free at the time of the survey. The need for surveillance was affirmed by the majority of patients (>95%), and one third stated that there was a need for more technical efforts during follow-up. In contrast to the follow-up guidelines, the results of the present survey indicated that most of the regularly scheduled follow-up visits were expanded using extensive laboratory and imaging procedures. Conclusion: This survey shows that the majority of physicians obviously do not accept the present follow-up guidelines. A new surveillance study investigating the efficacy of an intensified surveillance based on the improved possibilities of modern diagnostics and endocrine, immunotherapeutic, chemotherapeutic and interventional treatment options is warranted
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