Climate and chemistry effects of a regional scale nuclear conflict

Previous studies have highlighted the severity of detrimental effects for life on earth after an assumed regionally limited nuclear war. These effects are caused by climatic, chemical and radiative changes persisting for up to one decade. However, so far only a very limited number of climate model simulations have been performed, giving rise to the question how realistic previous computations have been. This study uses the coupled chemistry climate model (CCM) SOCOL, which belongs to a different family of CCMs than previously used, to investigate the consequences of such a hypothetical nuclear conflict. In accordance with previous studies, the present work assumes a scenario of a nuclear conflict between India and Pakistan, each applying 50 warheads with an individual blasting power of 15 kt ("Hiroshima size") against the major population centers, resulting in the emission of tiny soot particles, which are generated in the firestorms expected in the aftermath of the detonations. Substantial uncertainties related to the calculation of likely soot emissions, particularly concerning assumptions of target fuel loading and targeting of weapons, have been addressed by simulating several scenarios, with soot emissions ranging from 1 to 12 Tg. Their high absorptivity with respect to solar radiation leads to a rapid self-lofting of the soot particles into the strato- and mesosphere within a few days after emission, where they remain for several years. Consequently, the model suggests earth's surface temperatures to drop by several degrees Celsius due to the shielding of solar irradiance by the soot, indicating a major global cooling. In addition, there is a substantial reduction of precipitation lasting 5 to 10 yr after the conflict, depending on the magnitude of the initial soot release. Extreme cold spells associated with an increase in sea ice formation are found during Northern Hemisphere winter, which expose the continental land masses of North America and Eurasia to a cooling of several degrees. In the stratosphere, the strong heating leads to an acceleration of catalytic ozone loss and, consequently, to enhancements of UV radiation at the ground. In contrast to surface temperature and precipitation changes, which show a linear dependence to the soot burden, there is a saturation effect with respect to stratospheric ozone chemistry. Soot emissions of 5 Tg lead to an ozone column reduction of almost 50% in northern high latitudes, while emitting 12 Tg only increases ozone loss by a further 10%. In summary, this study, though using a different chemistry climate model, corroborates the previous investigations with respect to the atmospheric impacts. In addition to these persistent effects, the present study draws attention to episodically cold phases, which would likely add to the severity of human harm worldwide. The best insurance against such a catastrophic development would be the delegitimization of nuclear weapons.

Subjective and objective perception of orthodontic treatment need: a systematic review

The aim of this work was to investigate the published evidence on the comparison of self-perception and diagnosis of orthodontic treatment need. A search of Cochrane Library, MEDLINE, Scopus databases, and archives of two orthodontic journals was carried out from January 1966 to August 2011 by the two authors using Medical Subject Heading terms. Studies that investigated solely either self-perception of orthodontic need by laypersons or assessment of orthodontic need by professionals were excluded from the data analysis. The methodological soundness of each study and the aggregate level of evidence were evaluated according to predetermined criteria. Moderate level of evidence, the relatively highest grade, was assigned to 9.1 per cent of the 22 studies, finally included in the data analysis. The overall evidence level provided by the evaluated publications was rated as limited. However, the existing body of evidence indicated a highly variable association between self-perception of orthodontic treatment need and orthodontist's assessment. Future controlled studies with well-defined samples and common assessment methodology will clarify further the relationship between perception of treatment need by laypersons and orthodontists and enhance international comparison and development of health care strategies.

Recent skin self-examination and doctor visits in relation to melanoma risk and tumour depth

BACKGROUND Little is known about the potential benefit of skin self-examination for melanoma prevention and early detection. Objectives: To determine whether skin self-examination is associated with reduced melanoma risk, self-detection of tumours, and reduced risk of deeper melanomas. METHODS We used data from a population-based case-control study (423 cases, 678 controls) to assess recent skin self-examination in relation to self-detection, melanoma risk and tumour depth ( ≤1 mm; > 1 mm). Logistic regression was used to estimate odds ratios (ORs) and confidence intervals (CIs) for associations of interest. RESULTS Skin self-examination conducted 1-11 times during a recent year was associated with a possible decrease in melanoma risk (OR 0·74; 95% CI 0·54-1·02). Melanoma risk was decreased for those who conducted skin self-examination and saw a doctor (OR 0·52; 95% CI 0·30-0·90). Among cases, those who examined their skin were twice as likely to self-detect the melanoma (OR 2·23; 95% CI 1·47-3·38), but self-detection was not associated with shallower tumours. Tumour depth was reduced for those who conducted skin self-examination 1-11 times during a recent year (OR 0·39; 95% CI 0·18-0·81), but was not influenced by seeing a doctor, or by conducting skin self-examination and seeing a doctor. CONCLUSIONS Risk of a deeper tumour and possibly risk of melanoma were reduced by skin self-examination 1-11 times annually. Melanoma risk was markedly reduced by skin self-examination coupled with a doctor visit. We cannot, however, exclude the possibility that our findings reflect bias or confounding. Additional studies are needed to elucidate the potential benefits of skin self-examination for melanoma prevention and early detection.

Selection and influence effects in defending a victim of bullying: The moderating effects of school context

In this paper we examined whether defenders of victims of school bullying befriended similar peers, and whether the similarity is due to selection or influence processes or both. We examined whether these processes result in different degrees of similarity between peers depending on teachers’ self-efficacy and the school climate. We analyzed longitudinal data of 478 Swiss school students employing actor-based stochastic models. Our analyses showed that similarity in defending behavior among friends was due to selection rather than influence. The extent to which adolescents selected peers showing similar defending behavior was related to contextual factors. In fact, lower self-efficacy of teachers and positive school climate were associated with increased selection effects in terms of defending behavior.

The role of zinc dynamics in growth hormone secretion

Human growth hormone (GH) causes a variety of physiological and metabolic effects in humans and plays a pivotal role in postnatal growth. In somatotroph cells of the anterior pituitary, GH is stored in concentrated forms in secretory granules to be rapidly released upon GH-releasing hormone stimulation. During the process of secretory granule biogenesis, self-association of GH occurs in the compartments of the early secretory pathway (endoplasmic reticulum and Golgi complex). Since this process is greatly facilitated by the presence of zinc ions, it is of importance to understand the potential role of zinc transporters that participate in the fine-tuning of zinc homeostasis and dynamics, particularly in the early secretory pathway. Thus, the role of zinc transporters in supplying the secretory pathway with the sufficient amount of zinc required for the biogenesis of GH-containing secretory granules is essential for normal secretion. This report, illustrated by a clinical case report on transient neonatal zinc deficiency, focuses on the role of zinc in GH storage in the secretory granules and highlights the role of specific zinc transporters in the early secretory pathway.

Design, synthesis and biological evaluation of 5$\sp\prime$-mononucleotide prodrugs: Strategies to introduce nucleotides into cells

The neutral bis ((pivaloyloxy)methyl) (PIV$\sb2\rbrack$ derivatives of FdUMP, ddUMP, and AZTMP were synthesized as potential membrane-permeable prodrugs of FdUMP, ddUMP, and AZTMP. These compounds were designed to enter cells by passive diffusion and revert to the parent nucleotides after removal of the PIV groups by hydrolytic enzymes. These prodrugs were prepared by condensation of FUdR, ddU, and AZT with PIV$\sb2$ phosphate in the presence of triphenylphosphine and diethyl azodicarboxylate (the Mitsunobo reagent). PIV$\sb2$-FdUMP, PIV$\sb2$-ddUMP, and PIV$\sb2$-AZTMP were stable in the pH range 1.0-4.0 (t$\sb{1/2} = {>}$100 h). They were also fairly stable at pH 7.4 (t$\sb{1/2} = {>}$40 h). In 0.05 M NaOH solution, however, they were rapidly degraded (t$\sb{1/2} < 2$ min). In the presence hog liver carboxylate esterase, they were converted quantitatively to the corresponding phosphodiesters, PIV$\sb1$-FdUMP, PIV$\sb1$-ddUMP, and PIV$\sb1$-AZTMP; after 24 h incubation, only trace amounts of FdUMP, ddUMP, and AZTMP (1-5%) were observed indicating that the PIV$\sb1$ compounds were poor substrates for the enzyme. In human plasma, the PIV$\sb2$ compounds were rapidly degraded with half-lives of less than 5 min. The rate of degradation of the PIV$\sb2$ compounds in the presence of phosphodiesterase I was the same as that in buffer controls, indicating that they were not substrates for this enzyme. In the presence of phosphodiesterase I, PIV$\sb1$-FdUMP, PIV$\sb1$-ddUMP, and PIV$\sb1$-AZTMP were converted quantitatively to FdUMP, ddUMP, and AZTMP.^ PIV$\sb2$-ddUMP and PIV$\sb2$-AZTMP were effective at controlling HIV type 1 infection in MT-4 and CEM tk$\sp-$ cells in culture. Mechanistic studies demonstrated that PIV$\sb2$-ddUMP and PIV$\sb2$-AZTMP were taken up by the cells and converted to ddUTP and AZTTP, both potent inhibitors of HIV reverse transcriptase. However, a potential shortcoming of PIV$\sb2$-ddUMP and PIV$\sb2$-AZTMP as clinical therapeutic agents is that they are rapidly degraded (t$\sb{1/2}$ = approx. 4 minutes) in human plasma by carboxylate esterases. To circumvent this limitation, chemically-labile nucleotide prodrugs and liposome-encapsulated nucleotide prodrugs were investigated. In the former approach, the protective groups bis(N, N-(dimethyl)carbamoyloxymethyl) (DM$\sb2$) and bis (N-(piperidino)carbamoyloxymethyl) (DP$\sb2$) were used to synthesize DM$\sb2$-ddUMP and DP$\sb2$-ddUMP, respectively. In aqueous buffers (pH range 1.0-9.0) these compounds were degraded with half-lives of 3 to 4 h. They had similar half-lives in human plasma demonstrating that they were resistant to esterase-mediated cleavage. However, neither compound gave rise to significant concentrations of ddUMP in CEM or CEM tk$\sp-$ cells. In the liposome-encapsulated nucleotide prodrug approach, three different liposomal formulations of PIV$\sb2$-ddUMP (L-PIV$\sb2$-ddUMP) were investigated. The half-lifes of these L-PIV$\sb2$-ddUMP preparations in human plasma were 2 h compared with 4 min for the free drug. The preparations were more effective at controlling HIV-1 infection than free PIV$\sb2$-ddUMP in human T cells in culture. Collectively, these data indicate that PIV$\sb2$-FdUMP, PIV$\sb2$-ddUMP, and PIV$\sb2$-AZTMP are effective membrane-permeable prodrugs of FdUMP, ddUMP, and AZTMP. ^

Studies of subcellular localization and complex formation of the Agrobacterium tumefaciens transport ATPase VirB11

The VirB11 ATPase is an essential component of an Agrobacterium tumefaciens type IV bacterial secretion system that transfers oncogenic nucleoprotein complexes to susceptible plant cells. This dissertation investigates the subcellular localization and homo-oligomeric state of the VirB11 ATPase in order to provide insights about the assembly of the protein as a subunit of this membrane-associated transfer system. Subcellular fractionation studies and quantitative immunoblot analysis demonstrated that $\sim$30% of VirB11 partitioned as soluble protein and $\sim$70% was tightly associated with the bacterial cytoplasmic membrane. No differences were detected in VirB11 subcellular localization and membrane association in the presence or absence of other transport system components. Mutations in virB11 affecting protein function were mapped near the amino terminus, just upstream of a region encoding a Walker 'A' nucleotide-binding site, and within the Walker 'A' motif partitioned almost exclusively with the cytoplasmic membrane, suggesting that an activity associated with nucleotide binding could modulate the affinity of VirB11 for the cytoplasmic membrane. Merodiploid analysis of VirB11 mutant and truncation derivatives provided strong evidence that VirB11 functions as a homo- or heteromultimer and that the C-terminal half of VirB11 contains a protein interaction domain. A combination of biochemical and molecular genetic approaches suggested that VirB11 and the green fluorescence protein (GFP) formed a mixed multimer as demonstrated by immunoprecipitation experiments with anti-GFP antibodies. Second, a hybrid protein composed of VirB11 fused to the N-terminal DNA-binding domain of bacteriophage $\lambda$ cI repressor conferred immunity to $\lambda$ superinfection, demonstrating that VirB11 self-association promotes dimerization of the chimeric repressor. A conserved Walker 'A' motif, though required for VirB11 function in T-complex export, was not necessary for VirB11 self-association. Sequences in both the N- and the C-terminal halves of the protein were found to contribute to self-association of the full length protein. Chemical cross-linking experiments with His$\sb6$ tagged VirB11 suggested that VirB11 probably assembles into a higher order homo-oligomeric complex. ^

The use of unmanned aerial vehicles and wireless sensor networks for spraying pesticides

The application of pesticides and fertilizers in agricultural areas is of crucial importance for crop yields. The use of aircrafts is becoming increasingly common in carrying out this task mainly because of their speed and effectiveness in the spraying operation. However, some factors may reduce the yield, or even cause damage (e.g., crop areas not covered in the spraying process, overlapping spraying of crop areas, applying pesticides on the outer edge of the crop). Weather conditions, such as the intensity and direction of the wind while spraying, add further complexity to the problem of maintaining control. In this paper, we describe an architecture to address the problem of self-adjustment of the UAV routes when spraying chemicals in a crop field. We propose and evaluate an algorithm to adjust the UAV route to changes in wind intensity and direction. The algorithm to adapt the path runs in the UAV and its input is the feedback obtained from the wireless sensor network (WSN) deployed in the crop field. Moreover, we evaluate the impact of the number of communication messages between the UAV and the WSN. The results show that the use of the feedback information from the sensors to make adjustments to the routes could significantly reduce the waste of pesticides and fertilizers.

Convolution roots and differentiability of isotropic positive definite functions on spheres

We prove that any isotropic positive definite function on the sphere can be written as the spherical self-convolution of an isotropic real-valued function. It is known that isotropic positive definite functions on d-dimensional Euclidean space admit a continuous derivative of order [(d − 1)/2]. We show that the same holds true for isotropic positive definite functions on spheres and prove that this result is optimal for all odd dimensions.

Diversity of morphological patterns in supramolecular polymers formed from the amphiphilic oligomers of pyrenes

Very important aspects of the modern nanotechnology are control and prediction of arraying patterns of opto- and electroactive molecules in discrete objects on nanoscale level both on surface and solution. Consequqntly, a self-assembly of small molucules provides such an opportunity.For example, oligopyrenotides (OPs, short amphiphilic pyrene oligomers) represent a novel class of amphiphilic molecules which tend to aggegate in aqueous phase. As has been already shown, OPs are able to form 1D supramolecular polymer only under high salt concentration. Since programmed arraying of polyaromatic hydrocarbons in structurally defined objects could offer enhanced performance over the individual components, prediction and controlling of their spatial arrangement remains challenging. Herein we demonstrate that substitution type of the pyrene is crutial, and it determines a morphology of the assemblies. Thus, a 1.6-linkage causes a formation of large, free-standing 2D supromolecular polymers with a thickness 2 nm. These assemblies possess a high degree of an internal order: the interior consists of hydrophobic pyrenes and alkyl chains, whereas the exterior exists as a net of hydrophilic negatively charged phosphates. Contrary, a 1.8-linkage exclusiveley leads to a formation of long (up to a few micrometer), nanometer thick helical supramolecular polymers. These structures tend to form even more complex structures (bundles, superhelixes). Moreover for both molecules, the polymerizations occurs via a nucleation-elongation mechanism. To study Py3 self-assembly, we carried out whole set of spectroscopic (UV/vis, fluorescence, DLS) and microscopic experiments (AFM).

ON THE STABILITY OF SUPER-EARTH ATMOSPHERES

We investigate the stability of super-Earth atmospheres around M stars using a seven-parameter, analytical framework. We construct stability diagrams in the parameter space of exoplanetary radius versus semimajor axis and elucidate the regions in which the atmospheres are stable against the condensation of their major constituents, out of the gas phase, on their permanent nightside hemispheres. We find that super-Earth atmospheres that are nitrogen-dominated (Earth-like) occupy a smaller region of allowed parameter space, compared to hydrogen-dominated atmospheres, because of the dual effects of diminished advection and enhanced radiative cooling. Furthermore, some super-Earths which reside within the habitable zones of M stars may not possess stable atmospheres, depending on the mean molecular weight and infrared photospheric pressure of their atmospheres. We apply our stability diagrams to GJ 436b and GJ 1214b, and demonstrate that atmospheric compositions with high mean molecular weights are disfavored if these exoplanets possess solid surfaces and shallow atmospheres. Finally, we construct stability diagrams tailored to the Kepler data set, for G and K stars, and predict that about half of the exoplanet candidates are expected to harbor stable atmospheres if Earth-like conditions are assumed. We include 55 Cancri e and CoRoT-7b in our stability diagram for G stars

Optical and scintillation properties of CsBa2I5:Eu2+

The scintillation and luminescence properties of pure CsBa2I5 and CsBa2I5 doped with 0.5% Eu and 5% Eu were studied between 78 K and 600 K. Single crystals were grown by the vertical Bridgman method from the melt. CsBa2I5:5% Eu showed a light yield of 80,000 photons/MeV, an energy resolution of 2.3% for the 662 key full absorption peak, and an excellent proportional response. Two broad emission bands centered at 400 nm and 600 nm were observed in the radioluminescence spectrum of pure CsBa2I5. The Eu2+ 5d-4f emission band was observed at 430 nm. The radiative lifetime of the Eu2+ excited state was determined as 350 ns. With increasing temperature and Eu concentration the Eu2+ emission shifts to longer wavelengths and its decay time lengthens as a result of self-absorption of the Eu2+ emission. Multiple thermoluminescence glow peaks and a sharp decrease of the light yield at temperatures below 200 K were observed and related to the presence of the charge carrier traps in CsBa2I5:Eu.

Factors influencing the attitudes of cattle veterinarians, farmers, and claw trimmers towards the pain associated with the treatment of sole ulcers and the sensitivity to pain of dairy cows

This study assessed the attitudes of personnel involved in therapeutic claw trimming of dairy cattle in Switzerland towards pain associated with sole ulcers and their treatment. Data from 77 farmers, 32 claw trimmers, and 137 cattle veterinarians were used. A large range of factors were associated with whether the respondents thought that anaesthesia during the treatment of sole ulcers was beneficial; these included year of graduation, work experience, attitude to costs of analgesia, perception of competition between veterinarians and claw trimmers, estimation of pain level associated with treatment, estimated sensitivity of dairy cows to pain, knowledge of the obligation to provide analgesia, and whether the respondent thought lesion size and occurrence of defensive behaviour by the cow were important. Respondents' estimation of the pain level associated with sole ulcer treatment was linked to frequency of therapeutic claw trimming, age, farmers' income, estimated knowledge of the benefits of analgesia, and estimated sensitivity of dairy cows to pain. The latter factor was associated with profession, frequency of therapeutic claw trimming, capability of pain recognition, opinion on the benefits of analgesia, knowledge of the obligation to provide analgesia, and self-estimation of the ability to recognise pain. Improving the knowledge of personnel involved in therapeutic claw trimming with regard to pain in dairy cows and how to alleviate it is crucial if management of pain associated with treatment of sole ulcer and the welfare of lame cows are to be optimised.

Courses in the language and culture of origin and their impact on youth development in cultural transition: A study among immigrant and dual heritage youth in Switzerland

Elena Makarova traces how the concept of intercultural education in German-speaking European countries promotes the inclusion of courses in the Language and Culture of Origin (LCO) for immigrant youth in the school curriculum of host countries. Such courses are assumed to have positive effects on the development of immigrant youth in the host country. Particularly, it has been suggested that participation in LCO courses increases the self-esteem of immigrant youth, facilitates the development of their bicultural identity and improves their integration in the host society. However, there is a lack of empirical evidence on the nature of the effects of LCO course attendance on the acculturation of immigrant youth and their cultural identity. Accordingly, the aim of the study detailed in the chapter is to examine the impact of immigrant youth’s attitudes towards LCO courses and of their attendance of such courses on their acculturation and cultural identity.

Head movement synchrony in social interactions of patients with schizophrenia indicates symptoms, cognition and social functioning

Background: Disturbed interpersonal communication is a core problem in schizophrenia. Patients with schizophrenia often appear disconnected and "out of sync" when interacting with others. This may involve perception, cognition, motor behavior, and nonverbal expressiveness. Although well-known from clinical observation, mainstream research has neglected this area. Corresponding theoretical concepts, statistical methods, and assessment were missing. In recent research, however, it has been shown that objective, video-based measures of nonverbal behavior can be used to reliably quantify nonverbal behavior in schizophrenia. Newly developed algorithms allow for a calculation of movement synchrony. We found that the objective amount of movement of patients with schizophrenia during social interactions was closely related to the symptom profiles of these patients (Kupper et al., 2010). In addition and above the mere amount of movement, the degree of synchrony between patients and healthy interactants may be indicative of various problems in the domain of interpersonal communication and social cognition. Methods: Based on our earlier study, head movement synchrony was assessed objectively (using Motion Energy Analysis, MEA) in 378 brief, videotaped role-play scenes involving 27 stabilized outpatients diagnosed with paranoid-type schizophrenia. Results: Lower head movement synchrony was indicative of symptoms (negative symptoms, but also of conceptual disorganization and lack of insight), verbal memory, patients’ self-evaluation of competence, and social functioning. Many of these relationships remained significant even when corrected for the amount of movement of the patients. Conclusion: The results suggest that nonverbal synchrony may be an objective and sensitive indicator of the severity of symptoms, cognition and social functioning.