Consequences of warming and resource quality on the stoichiometry and nutrient cycling of a stream shredder

As a result of climate change, streams are warming and their runoff has been decreasing in most temperate areas. These changes can affect consumers directly by increasing their metabolic rates and modifying their physiology and indirectly by changing the quality of the resources on which organisms depend. In this study, a common stream detritivore (Echinogammarus berilloni Catta) was reared at two temperatures (15 and 20°C) and fed Populus nigra L. leaves that had been conditioned either in an intermittent or permanent reach to evaluate the effects of resource quality and increased temperatures on detritivore performance, stoichiometry and nutrient cycling. The lower quality (i.e., lower protein, soluble carbohydrates and higher C:P and N:P ratios) of leaves conditioned in pools resulted in compensatory feeding and lower nutrient retention capacity by E. berilloni. This effect was especially marked for phosphorus, which was unexpected based on predictions of ecological stoichiometry. When individuals were fed pool-conditioned leaves at warmer temperatures, their growth rates were higher, but consumers exhibited less efficient assimilation and higher mortality. Furthermore, the shifts to lower C:P ratios and higher lipid concentrations in shredder body tissues suggest that structural molecules such as phospholipids are preserved over other energetic C-rich macromolecules such as carbohydrates. These effects on consumer physiology and metabolism were further translated into feces and excreta nutrient ratios. Overall, our results show that the effects of reduced leaf quality on detritivore nutrient retention were more severe at higher temperatures because the shredders were not able to offset their increased metabolism with increased consumption or more efficient digestion when fed pool-conditioned leaves. Consequently, the synergistic effects of impaired food quality and increased temperatures might not only affect the physiology and survival of detritivores but also extend to other trophic compartments through detritivore-mediated nutrient cycling.

Clinical consequences of switching from olanzapine to risperidone and vice versa in outpatients with schizophrenia: 36-month results from the worldwide schizophrenia outpatients health outcomes (W-SOHO) study

BACKGROUND: With many atypical antipsychotics now available in the market, it has become a common clinical practice to switch between atypical agents as a means of achieving the best clinical outcomes. This study aimed to examine the impact of switching from olanzapine to risperidone and vice versa on clinical status and tolerability outcomes in outpatients with schizophrenia in a naturalistic setting. METHODS: W-SOHO was a 3-year observational study that involved over 17,000 outpatients with schizophrenia from 37 countries worldwide. The present post hoc study focused on the subgroup of patients who started taking olanzapine at baseline and subsequently made the first switch to risperidone (n=162) and vice versa (n=136). Clinical status was assessed at the visit when the first switch was made (i.e. before switching) and after switching. Logistic regression models examined the impact of medication switch on tolerability outcomes, and linear regression models assessed the association between medication switch and change in the Clinical Global Impression-Schizophrenia (CGI-SCH) overall score or change in weight. In addition, Kaplan-Meier survival curves and Cox-proportional hazards models were used to analyze the time to medication switch as well as time to relapse (symptom worsening as assessed by the CGI-SCH scale or hospitalization). RESULTS: 48% and 39% of patients switching to olanzapine and risperidone, respectively, remained on the medication without further switches (p=0.019). Patients switching to olanzapine were significantly less likely to experience relapse (hazard ratio: 3.43, 95% CI: 1.43, 8.26), extrapyramidal symptoms (odds ratio [OR]: 4.02, 95% CI: 1.49, 10.89) and amenorrhea/galactorrhea (OR: 8.99, 95% CI: 2.30, 35.13). No significant difference in weight change was, however, found between the two groups. While the CGI-SCH overall score improved in both groups after switching, there was a significantly greater change in those who switched to olanzapine (difference of 0.29 points, p=0.013). CONCLUSION: Our study showed that patients who switched from risperidone to olanzapine were likely to experience a more favorable treatment course than those who switched from olanzapine to risperidone. Given the nature of observational study design and small sample size, additional studies are warranted.

Predictors and consequences of adherence to the treatment of pediatric patients with attention-deficit/hyperactivity disorder in Central Europe and East Asia.

PURPOSE: To assess baseline predictors and consequences of medication non-adherence in the treatment of pediatric patients with attention-deficit/hyperactivity disorder (ADHD) from Central Europe and East Asia. PATIENTS AND METHODS: Data for this post-hoc analysis were taken from a 1-year prospective, observational study that included a total of 1,068 newly-diagnosed pediatric patients with ADHD symptoms from Central Europe and East Asia. Medication adherence during the week prior to each visit was assessed by treating physicians using a 5-point Likert scale, and then dichotomized into either adherent or non-adherent. Clinical severity was measured by the Clinical Global Impressions-ADHD-Severity (CGI-ADHD) scale and the Child Symptom Inventory-4 (CSI-4) Checklist. Health-Related Quality of Life (HRQoL) was measured using the Child Health and Illness Profile-Child Edition (CHIP-CE). Regression analyses were used to assess baseline predictors of overall adherence during follow-up, and the impact of time-varying adherence on subsequent outcomes: response (defined as a decrease of at least 1 point in CGI), changes in CGI-ADHD, CSI-4, and the five dimensions of CHIP-CE. RESULTS: Of the 860 patients analyzed, 64.5% (71.6% in Central Europe and 55.5% in East Asia) were rated as adherent and 35.5% as non-adherent during follow-up. Being from East Asia was found to be a strong predictor of non-adherence. In East Asia, a family history of ADHD and parental emotional distress were associated with non-adherence, while having no other children living at home was associated with non-adherence in Central Europe as well as in the overall sample. Non-adherence was associated with poorer response and less improvement on CGI-ADHD and CSI-4, but not on CHIP-CE. CONCLUSION: Non-adherence to medication is common in the treatment of ADHD, particularly in East Asia. Non-adherence was associated with poorer response and less improvement in clinical severity. A limitation of this study is that medication adherence was assessed by the treating clinician using a single item question.

Cytoplasmic accumulation of NCoR in malignant melanoma: Consequences of altered gene repression and prognostic significance

Invasive malignant melanoma (MM) is an aggressive tumor with no curative therapy available in advanced stages. Nuclear corepressor (NCoR) is an essential regulator of gene transcription, and its function has been found deregulated in different types of cancer. In colorectal cancer cells, loss of nuclear NCoR is induced by Inhibitor of kappa B kinase (IKK) through the phosphorylation of specific serine residues. We here investigate whether NCoR function impacts in MM, which might have important diagnostic and prognostic significance. By IHC, we here determined the subcellular distribution of NCoR in a cohort of 63 primary invasive MM samples, and analyzed its possible correlation with specific clinical parameters. We therefore used a microarray-based strategy to determine global gene expression differences in samples with similar tumor stage, which differ in the presence of cytoplasmic or nuclear NCoR. We found that loss of nuclear NCoR results in upregulation of a specific cancer-related genetic signature, and is significantly associated with MM progression. Inhibition of IKK activity in melanoma cells reverts NCoR nuclear distribution and specific NCoR-regulated gene transcription. Analysis of public database demonstrated that inactivating NCoR mutations are highly prevalent in MM, showing features of driver oncogene.

De-escalation of commitment management strategy in IT project management methodology: case of ERP implementation project by IT consulting company

According to several surveys and observations, the percentage of successfully conducted IT projects without over-budgeting and delays in time schedule are extremely low. Many projects also are evaluated as failures in terms of delivered functionality. Nuldén (1996) compares IT projects with bad movies; after watching for 2 hours, one still tries to finish it even though one understands that it is a complete waste of time. The argument for that is 'I've already invested too much time to terminate it now'. The same happens with IT projects: sometimes the company continues wasting money on these projects for a long time, even though there are no expected benefits from these projects. Eventually these projects are terminated anyway, but until this moment, the company spends a lot. The situation described above is a consequence of “escalation of commitment” - project continuation even after a manager receives negative feedback of the project’s success probability. According to Keil and Mähring (2010), even though escalation can occur in any type of project, it is more common among complex technological projects, such as IT projects. Escalation of commitment very often results in runaway projects. In order to avoid it, managers use de-escalation strategies, which allow the resources to be used in more effective. These strategies lead to project termination or turning around, which stops the flow of wasted investments. Numbers of researches explore escalation of commitment phenomena based on experiments and business cases. Moreover, during the last decade several frameworks were proposed for de-escalation strategy. However, there is no evidence of successful implementation of the de-escalation of commitment strategy in the literature. In addition, despite that fact that IT project management methodologies are widely used in the companies, none of them cover the topic of escalation of commitment risks. At the same time, there are no researches proposing the way to implement de-escalation of commitment strategy into the existing project management methodology The research is focused on a single case of large ERP implementation project by the consulting company. Hence, the main deliverables of the study include suggestions of improvement in de-escalation methods and techniques in the project and in the company. Moreover, the way to implement these methods into existing project management methodology and into the company general policies is found.

Training executive functions in the laboratory and in real life : cognitive consequences of computer-based exercises and bilingualism

The question of the trainability of executive functions and the impact of such training on related cognitive skills has stirred considerable research interest. Despite a number of studies investigating this, the question has not yet been solved. The general aim of this thesis was to investigate two very different types of training of executive functions: laboratory-based computerized training (Studies I-III) and realworld training through bilingualism (Studies IV-V). Bilingualism as a kind of training of executive functions is based on the idea that managing two languages requires executive resources, and previous studies have suggested a bilingual advantage in executive functions. Three executive functions were studied in the present thesis: updating of working memory (WM) contents, inhibition of irrelevant information, and shifting between tasks and mental sets. Studies I-III investigated the effects of computer-based training of WM updating (Study I), inhibition (Study II), and set shifting (Study III) in healthy young adults. All studies showed increased performance on the trained task. More importantly, improvement on an untrained task tapping the trained executive function (near transfer) was seen in Study I and II. None of the three studies showed improvement on untrained tasks tapping some other cognitive function (far transfer) as a result of training. Study I also used PET to investigate the effects of WM updating training on a neurotransmitter closely linked to WM, namely dopamine. The PET results revealed increased striatal dopamine release during WM updating performance as a result of training. Study IV investigated the ability to inhibit task-irrelevant stimuli in bilinguals and monolinguals by using a dichotic listening task. The results showed that the bilinguals exceeded the monolinguals in inhibiting task-irrelevant information. Study V introduced a new, complementary research approach to study the bilingual executive advantage and its underlying mechanisms. To circumvent the methodological problems related to natural groups design, this approach focuses only on bilinguals and examines whether individual differences in bilingual behavior correlate with executive task performances. Using measures that tap the three above-entioned executive functions, the results suggested that more frequent language switching was associated with better set shifting skills, and earlier acquisition of the second language was related to better inhibition skills. In conclusion, the present behavioral results showed that computer-based training of executive functions can improve performance on the trained task and on closely related tasks, but does not yield a more general improvement of cognitive skills. Moreover, the functional neuroimaging results reveal that WM training modulates striatal dopaminergic function, speaking for training-induced neural plasticity in this important neurotransmitter system. With regard to bilingualism, the results provide further support to the idea that bilingualism can enhance executive functions. In addition, the new complementary research approach proposed here provides some clues as to which aspects of everyday bilingual behavior may be related to the advantage in executive functions in bilingual individuals.

The consequences of e-HRM on line managers

The purpose of this research was to provide a deeper insight into the consequences of electronic human resource management (e-HRM) for line managers. The consequences are viewed as used information system (IS) potentials pertaining to the moderate voluntaristic category of consequences. Due to the need to contextualize the research and draw on line managers’ personal experiences, a qualitative approach in a case study setting was selected. The empirical part of the research is loosely based on literature on HRM and e-HRM and it was conducted in an industrial private sector company. In this thesis, method triangulation was utilized, as nine semi-structured interviews, conducted in a European setting, created the main method for data collection and analysis. Other complementary data such as HRM documentation and statistics of e-HRM system usage were utilized as background information to help to put the results into context. E-HRM has partly been taken into use in the case study company. Line managers tend to use e-HRM when a particular task requires it, but they are not familiar with all the features and possibilities which e-HRM has to offer. The advantages of e-HRM are in line with the company’s goals. The advantages are e.g. an transparency of data, process consistency, and having an efficient and easy-to-use tool at one’s disposal. However, several unintended, even contradictory, and mainly negative outcomes can also be identified, such as over-complicated processes, in-security in use of the tool, and the lack of co-operation with HR professionals. The use of e-HRM and managers’ perceptions regarding e-HRM affect the way in which managers perceive the consequences of e-HRM on their work. Overall, the consequences of e-HRM are divergent, even contradictory. The managers who considered e-HRM mostly beneficial to their work found that e-HRM affects their work by providing information and increasing efficiency. Those managers who mostly perceived challenges in e-HRM did not think that e-HRM had affected their role or their work. Even though the perceptions regarding e-HRM and its consequences might reflect the strategies, the distribution of work, and the ways of working in all HRM in general and can’t be generalized as such, this research contributed to the field of e-HRM and it provides new perspectives to e-HRM in the case study organization and in the academic field in general.

Contested dominance modifies the anovulatory consequences of social subordination in female marmosets

Dominance status among female marmosets is reflected in agonistic behavior and ovarian function. Socially dominant females receive submissive behavior from subordinates, while exhibiting normal ovulatory function. Subordinate females, however, receive agonistic behavior from dominants, while exhibiting reduced or absent ovulatory function. Such disparity in female fertility is not absolute, and groups with two breeding females have been described. The data reported here were obtained from 8 female-female pairs of captive female marmosets, each housed with a single unrelated male. Pairs were classified into two groups: "uncontested" dominance (UD) and "contested" dominance (CD), with 4 pairs each. Dominant females in UD pairs showed significantly higher frequencies (4.1) of agonism (piloerection, attack and chasing) than their subordinates (0.36), and agonistic behaviors were overall more frequently displayed by CD than by UD pairs. Subordinates in CD pairs exhibited more agonistic behavior (2.9) than subordinates in UD pairs (0.36), which displayed significantly more submissive (6.97) behaviors than their dominants (0.35). The data suggest that there is more than one kind of dominance relationship between female common marmosets. Assessment of progesterone levels showed that while subordinates in UD pairs appeared to be anovulatory, the degree of ovulatory disruption in subordinates of CD pairs was more varied and less complete. We suggest that such variation in female-female social dominance relationships and the associated variation in the degree and reliability of fertility suppression may explain variations of the reproductive condition of free-living groups of common marmosets.

Consequences of cerebroventricular insulin injection on renal sodium handling in rats: effect of inhibition of central nitric oxide synthase

In the present study, we investigated the effects of acute intracerebroventricular (icv) insulin administration on central mechanisms regulating urinary sodium excretion in simultaneously centrally NG-nitro-L-arginine methylester (L-NAME)-injected unanesthetized rats. Male Wistar-Hannover rats were randomly assigned to one of five groups: a) icv 0.15 M NaCl-injected rats (control, N = 10), b) icv dose-response (1.26, 12.6 and 126 ng/3 µL) insulin-injected rats (N = 10), c) rats icv injected with 60 µg L-NAME in combination with NaCl (N = 10) or d) with insulin (N = 10), and e) subcutaneously insulin-injected rats (N = 5). Centrally administered insulin produced an increase in urinary output of sodium (NaCl: 855.6 ± 85.1 Δ%/min; 126 ng insulin: 2055 ± 310.6 Δ%/min; P = 0.005) and potassium (NaCl: 460.4 ± 100 Δ%/min; 126 ng insulin: 669.2 ± 60.8 Δ%/min; P = 0.025). The urinary sodium excretion response to icv 126 ng insulin microinjection was significantly attenuated by combined administration of L-NAME (126 ng insulin: 1935 ± 258.3 Δ%/min; L-NAME + 126 ng insulin: 582.3 ± 69.6 Δ%/min; P = 0.01). Insulin-induced natriuresis occurred by increasing post-proximal sodium excretion, despite an unchanged glomerular filtration rate. Although the rationale for decreased urinary sodium excretion induced by combined icv L-NAME and insulin administration is unknown, it is tempting to suggest that perhaps one of the efferent signals triggered by insulin in the CNS may be nitrergic in nature.

Acute electrophysiologic consequences of pyridostigmine inhibition of cholinesterase in humans

The cardiovascular electrophysiologic basis for the action of pyridostigmine, an acetylcholinesterase inhibitor, has not been investigated. The objective of the present study was to determine the cardiac electrophysiologic effects of a single dose of pyridostigmine bromide in an open-label, quasi-experimental protocol. Fifteen patients who had been indicated for diagnostic cardiac electrophysiologic study underwent two studies just before and 90-120 min after the oral administration of pyridostigmine (45 mg). Pyridostigmine was well tolerated by all patients. Wenckebach nodal anterograde atrioventricular point and basic cycle were not altered by pyridostigmine. Sinus recovery time (ms) was shorter during a 500-ms cycle stimulation (pre: 326 ± 45 vs post: 235 ± 47; P = 0.003) but not during 400-ms (pre: 275 ± 28 vs post: 248 ± 32; P = 0.490) or 600-ms (pre: 252 ± 42 vs post: 179 ± 26; P = 0.080) cycle stimulation. Pyridostigmine increased the ventricular refractory period (ms) during the 400-ms cycle stimulation (pre: 238 ± 7 vs post: 245 ± 9; P = 0.028) but not during the 500-ms (pre: 248 ± 7 vs post: 253 ± 9; P = 0.150) or 600-ms (pre: 254 ± 8 vs post: 259 ± 8; P = 0.255) cycle stimulation. We conclude that pyridostigmine did not produce conduction disturbances and, indeed, increased the ventricular refractory period at higher heart rates. While the effect explains previous results showing the anti-arrhythmic action of pyridostigmine, the clinical impact on long-term outcomes requires further investigation.

Macroalgal Defenses Against Herbivory: Causes and Consequences of Intraspecific Variation

In marine benthic communities, herbivores consume a considerable proportion of primary producer biomass and, thus, generate selection for the evolution of resistance traits. According to the theory of plant defenses, resistance traits are costly to produce and, consequently, inducible resistance traits are adaptive in conditions of variable herbivory, while in conditions of constant/strong herbivory constitutive resistance traits are selected for. The evolution of resistance plasticity may be constrained by the costs of resistance or lack of genetic variation in resistance. Furthermore, resource allocation to induced resistance may be affected by higher trophic levels preying on herbivores. I studied the resistance to herbivory of a foundation species, the brown alga Fucus vesiculosus. By using factorial field experiments, I explored the effects of herbivores and fish predators on growth and resistance of the alga in two seasons. I explored genetic variation in and allocation costs of resistance traits as well as their chemical basis and their effects on herbivore performance. Using a field experiment I tested if induced resistance spreads via water-borne cues from one individual to another in relevant ecological conditions. I found that in the northern Baltic Sea F. vesiculosus communities, strength of three trophic interactions strongly vary among seasons. The highly synchronized summer reproduction of herbivores promoted their escape from the top-down control of fish predators in autumn. This resulted into large grazing losses in algal stands. In spring, herbivore densities were low and regulated by fish, which, thus,enhanced algal growth. The resistance of algae to herbivory increased with an increase in constitutive phlorotannin content. Furthermore, individuals adopted induced resistance when grazed and when exposed to water-borne cues originating from grazing of conspecific algae both in the laboratory and in field conditions. Induced resistance was adopted to a lesser extent in the presence of fish predators. The results in this thesis indicate that inducible resistance in F. vesiculosus is an adaptation to varying herbivory in the northern Baltic Sea. The costs of resistance and strong seasonality of herbivory have likely contributed to the evolution of this defense strategy. My findings also show that fish predators have positive cascading effects on F. vesiculosus which arise via reduced herbivory but possibly also through reduced resource allocation to resistance. I further found evidence that the spread of resistance via water-borne cues also occurs in ecologically realistic conditions in natural marine sublittoral. Thus, water-borne induction may enable macroalgae to cope with the strong grazing pressure characteristic of marine benthic communities. The results presented here show that seasonality can have pronounced effects on the biotic interactions in marine benthic communities and thereafter influence the evolution of resistance traits in primary producers.