Cadmium-induced turion formation of Spirodela polyrhiza (L.) Schleiden

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Cadmium-induced turion formation of Spirodela polyrhiza (L.) Schleiden

Spirodela polyrhiza (L.) Schleiden (giant duckweed) is an extensively studied representative of duckweeds (Lemnoideae subfamily, Araceae). Despite its widespread application in numerous research areas and well-known capability for producing turions, the effects of various toxicants on turion production are sporadically discussed in the scientific literature. Our aim was to study the growth of S. polyrhiza under cadmium stress and to test its potential interference with turion production. Effects of cadmium were assessed in axenic cultures of a local S. polyrhiza clone in 7-days-long duckweed growth inhibition tests. Our results indicated that higher cadmium concentrations decreased the relative growth rates of cultures within 3 days and growth inhibition reached its maximum between the 3rd and 5th days with 0.080 mg l-1 IC50. Parallel with slowed frond production - by mirror image pattern - induction of turion formation was observed. The first turions protruded by the 5th day of treatments in the 0.075-0.75 mg l-1 concentration range. Such rapid onset of turion formation is indicative of an almost immediate switch between normal and turion mode of meristem function upon cadmium stress. The consideration of this mechanism in practical applications of S. polyrhiza is recommended

Seclusion as a coercive measure in suicidality – daily routine or exception?

Background: Coercive measures continue to be an important topic in psychiatry. However, there is no proof of the effectiveness of the use of coercive measures, especially with suicidal people. For many years, attempts have been made to replace such measures with alternative noncoercive intervention options. This paper aims to clarify the situation of coercive measures, more precisely seclusions, in a general psychiatric hospital in Switzerland. It focuses on compulsory measures in patients with suicidal tendencies. Method: In this single-centre retrospective cohort study, we used routinely collected medical data and performed qualitative analyses of medical histories to examine whether alternative measures to seclusion had been offered and/or provided to patients who had been secluded solely because of suicidality. Patients were aged 18-65 years and had received inpatient treatment at one of five adult acute care units at a general psychiatric hospital in Switzerland between September 2016 and December 2019. Results: There were 5,935 inpatient treatment cases during the study period. Suicidality was rated as "acute" or "very high" at least once during the hospitalization in 219 (3.7%) cases. Of these, 60 were excluded from further analyses as they involved seclusion, but suicidality was not the exclusive indication for this measure. Coercive seclusion was imposed exclusively due to suicidality in 53 (33.3%) of the remaining 159 cases, whereas 106 (66.7%) cases were not secluded. The rates of seclusion among suicidal patients varied considerably between the hospital wards (13.0% to 55.3%). Suicidal patients with non-Swiss residence status and/or lacking language skills were particularly prone to be secluded. Additionally, alternative interventions were offered and provided significantly more frequently in the nonsecluded patients. Conclusions: To avoid seclusion due to suicidal tendencies, it is necessary to have a general attitude of avoiding coercive measures at all costs. It is also important for qualified staff to be able to deal with challenging sociodemographic characteristics of patients such as foreign-language, which may require translators and intercultural interpreters. Keywords: Coercive measures; Seclusion; Suicidality

Long-Term Follow-Up of Transsexual Persons Undergoing Sex Reassignment Surgery: Cohort Study in Sweden

CONTEXT: The treatment for transsexualism is sex reassignment, including hormonal treatment and surgery aimed at making the person's body as congruent with the opposite sex as possible. There is a dearth of long term, follow-up studies after sex reassignment. OBJECTIVE: To estimate mortality, morbidity, and criminal rate after surgical sex reassignment of transsexual persons. DESIGN: A population-based matched cohort study. SETTING: Sweden, 1973-2003. PARTICIPANTS: All 324 sex-reassigned persons (191 male-to-females, 133 female-to-males) in Sweden, 1973-2003. Random population controls (10:1) were matched by birth year and birth sex or reassigned (final) sex, respectively. MAIN OUTCOME MEASURES: Hazard ratios (HR) with 95% confidence intervals (CI) for mortality and psychiatric morbidity were obtained with Cox regression models, which were adjusted for immigrant status and psychiatric morbidity prior to sex reassignment (adjusted HR [aHR]). RESULTS: The overall mortality for sex-reassigned persons was higher during follow-up (aHR 2.8; 95% CI 1.8-4.3) than for controls of the same birth sex, particularly death from suicide (aHR 19.1; 95% CI 5.8-62.9). Sex-reassigned persons also had an increased risk for suicide attempts (aHR 4.9; 95% CI 2.9-8.5) and psychiatric inpatient care (aHR 2.8; 95% CI 2.0-3.9). Comparisons with controls matched on reassigned sex yielded similar results. Female-to-males, but not male-to-females, had a higher risk for criminal convictions than their respective birth sex controls. CONCLUSIONS: Persons with transsexualism, after sex reassignment, have considerably higher risks for mortality, suicidal behaviour, and psychiatric morbidity than the general population. Our findings suggest that sex reassignment, although alleviating gender dysphoria, may not suffice as treatment for transsexualism, and should inspire improved psychiatric and somatic care after sex reassignment for this patient group

Search for CP Violation in the Decay Z -> b (b bar) g

About three million hadronic decays of the Z collected by ALEPH in the years 1991-1994 are used to search for anomalous CP violation beyond the Standard Model in the decay Z -> b \bar{b} g. The study is performed by analyzing angular correlations between the two quarks and the gluon in three-jet events and by measuring the differential two-jet rate. No signal of CP violation is found. For the combinations of anomalous CP violating couplings, ${\hat{h}}_b = {\hat{h}}_{Ab}g_{Vb}-{\hat{h}}_{Vb}g_{Ab}$ and $h^{\ast}_b = \sqrt{\hat{h}_{Vb}^{2}+\hat{h}_{Ab}^{2}}$, limits of \hat{h}_b < 0.59$and$h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st

Global Patterns and Controls of Nutrient Immobilization On Decomposing Cellulose In Riverine Ecosystems

Microbes play a critical role in plant litter decomposition and influence the fate of carbon in rivers and riparian zones. When decomposing low-nutrient plant litter, microbes acquire nitrogen (N) and phosphorus (P) from the environment (i.e., nutrient immobilization), and this process is potentially sensitive to nutrient loading and changing climate. Nonetheless, environmental controls on immobilization are poorly understood because rates are also influenced by plant litter chemistry, which is coupled to the same environmental factors. Here we used a standardized, low-nutrient organic matter substrate (cotton strips) to quantify nutrient immobilization at 100 paired stream and riparian sites representing 11 biomes worldwide. Immobilization rates varied by three orders of magnitude, were greater in rivers than riparian zones, and were strongly correlated to decomposition rates. In rivers, P immobilization rates were controlled by surface water phosphate concentrations, but N immobilization rates were not related to inorganic N. The N:P of immobilized nutrients was tightly constrained to a molar ratio of 10:1 despite wide variation in surface water N:P. Immobilization rates were temperature-dependent in riparian zones but not related to temperature in rivers. However, in rivers nutrient supply ultimately controlled whether microbes could achieve the maximum expected decomposition rate at a given temperature

Search for R-Parity Violating Decays of Supersymmetric Particles in e+e−e^{+}e^{-} Collisions at Centre-of-Mass Energies near 183 GeV

Searches for pair-production of supersymmetric particles under the assumption that R-parity is violated via a single dominant $LL{\bar E}$, $LQ{\bar D}$ or ${\bar U} {\bar D} {\bar D}$ coupling are performed using the data collected by the \ALEPH\ collaboration at centre-of-mass energies of 181--184~\gev. The observed candidate events in the data are in agreement with the Standard Model expectations. Upper limits on the production cross-sections and lower limits on the masses of charginos, sleptons, squarks and sneutrinos are de rived