Investigating the Performance of Convection-Allowing Hindcast Simulations during the North American Monsoon with and without GPS-PWV Data Assimilation

The North American monsoon (NAM) is responsible for summer severe weather in the Southwest U.S. and northwest Mexico and its associated rainfall contributes the highest percentage of yearly precipitation to this region. Short-term convection-allowing model forecasts have shown difficultly in replicating the diurnal cycle of NAM convective precipitation. Generally, convection initiating over the Sierra Madre Occidental (SMO) mountain range in the early afternoon may later organize into mesoscale convective systems (MCSs) that propagate west towards the lower elevations and Gulf of California (GOC). MCSs account for the greatest proportion of all NAM-related precipitation. In my dissertation, I investigate the performance of daily short-term WRF hindcasts on moisture and precipitation with and without the assimilation of precipitable water vapor (PWV) measurements from Global Positioning System (GPS) ground receivers in the NAM GPS Transect Experiment 2013. In Chapter 2.1, I investigate the overall performance of daily hindcasts during the 2013 monsoon season without data assimilation. The 2.5-km convection-allowing hindcasts consistently display a moist bias in their initial conditions compared to GPS-PWV observations; this leads to diurnal convection beginning 3-6 hours earlier than observations. Because the precipitation forecast skill varies with the proximity of an inverted trough (IV), I compare the days when an IV is present (“strongly forced”) to days when an IV is not present (“weakly forced”). I find that strongly forced days display higher precipitation forecast skill than weakly forced days especially in the slopes of the northern SMO west of the crest that is associated with MCSs. In a case study spanning 8-9 July 2013, when nearly identical MCSs evolved over northern Sonora on consecutive days, the MCS is poorly simulated on the first day (weakly forced) when the IV is east of the SMO while a salient MCS is simulated on the second day (strongly forced) when that IV is over the SMO. I find a greater ensemble-based sensitivity to the initial specification of PWV for the weakly forced day when compared to the strongly forced day. Therefore, GPS-PWV data assimilation has the potential to benefit weakly forced days the most. In Chapter 2.2, for the weakly forced day (8 July 2013), I explore the impact of ensemble data assimilation of GPS-PWV observations to the model fields and the hindcast simulation of an MCS that occurred 9-15 hours after forecast initialization. I find that GPS-PWV DA improves location and intensity of the MCS. For all experiments, the GPS-PWV DA reduces the PWV root-mean-square-error to within the GPS-PWV observation error of 1-2 mm at initialization and reduces the initial wet bias. Although there is a short “memory” of these adjustments in that the PWV RMSE across the sites rises quickly and approaches the RMSE of the non-DA experiment after 2 hours, this is due to advective effects near the GOC in that the adjustments move quickly away or toward the sites. Assimilating GPS-PWV observations lowers the moisture (water vapor mixing ratio) error in the lower atmosphere to where is it within the instrument error aboard the radiosonde. From my sensitivity analyses, I conclude that increasing the covariance localization cutoff radius improves the MCS when adjusting all state variables but degrades it when adjusting only thermodynamic variables. Also, I recommend assimilating a mean hourly observation (“superobbing”) rather than individual 5-min observations as it allows for more stable adjustments. Lastly, I note that having a 12-h spin-up improves the MCS simulation because the initial conditions have a chance to make their way to the convection-allowing grid before GPS-PWV DA adjusts the MCS towards the observation. In a region of complex terrain that suffers from unreliable observations and poor convective forecasts during the NAM, I have shown utility from GPS-PWV observations in a) the diagnosis of wet model bias, b) the improvement of the initial conditions via convection-allowing ensemble data assimilation, and c) the improvement of MCS simulation. The results of this dissertation point to a need for more observations in the vertical and a deeper understanding of sensitivities of atmospheric variables to one another, such as what can be gained with with a network of ground-based lidars that continuously monitor the boundary layer

It Depends on the Size: How Firm Strategic Emphasis on Digital Transformation Predicts Market Capitalization

Whereas digital businesses can have an enormous market value, it remains an open question, whether firms, embarking on a digital transformation journey, can realize similar benefits. Thus, we rely on the signaling theory to study, whether strategic emphasis on digital transformation – i.e., the extent, to which a firm focuses on digital transformation in its strategy – as well as firm size as an indicator of a large resource basis jointly influence market capitalization. To answer this question, we conducted a longitudinal panel data analysis of the largest German publicly listed companies from 2000 to 2017. Our results show, that strategic emphasis on digital transformation leads to a higher market capitalization for larger firms and to a lower market capitalization for smaller firms. Whereas larger firms should further disclose their strategic emphasis on digital transformation, smaller firms should consider sending additional signals to investors, demonstrating their ability to undergo digital transformation successfully

Dekompozicijski prostori

Ovaj diplomski rad podijeljen je na tri poglavlja. U prvom poglavlju definirani su osnovni pojmovi kao što su topologija, topološki prostor i baza topologije. Drugo se poglavlje sastoji od same teme ovog diplomskog rada, odnosno govori o dekompozicijskim prostorima. Ovdje je definirana dekompozicijska topologija, dekompozicijski prostori te su dani mnogobrojni primjeri navedenih prostora. Također, ovdje se govori i o Hausdorffovim prostorima. U trećem, završnom poglavlju, proučavan je poseban slučaj dekompozicijskog prostora koji se naziva kvocijentni prostor, točnije kvocijent topološkog prostora i skupa. Definirano je dekompozicijsko preslikavanje kao i kompaktnost te proučavana neka njihova svojstva.This diploma thesis is divided in three chapters. Basic notions like topology, topological space and basis of topology are defined in the first chapter. The second chapter consists of the theme of this diploma thesis, more exactly it is talking about decomposition spaces. Decomposition topology and decomposition spaces are defined here and numerous examples of such spaces are given. This chapter also speaks of Hausdorff spaces. In third, final chapter, a special case of decomposition space is analyzed, also known as quotient space, more precisely quotient of topological space and set. Decomposition map is also defined here, as well as compactness and some of their properties

Dekompozicijski prostori

Ovaj diplomski rad podijeljen je na tri poglavlja. U prvom poglavlju definirani su osnovni pojmovi kao što su topologija, topološki prostor i baza topologije. Drugo se poglavlje sastoji od same teme ovog diplomskog rada, odnosno govori o dekompozicijskim prostorima. Ovdje je definirana dekompozicijska topologija, dekompozicijski prostori te su dani mnogobrojni primjeri navedenih prostora. Također, ovdje se govori i o Hausdorffovim prostorima. U trećem, završnom poglavlju, proučavan je poseban slučaj dekompozicijskog prostora koji se naziva kvocijentni prostor, točnije kvocijent topološkog prostora i skupa. Definirano je dekompozicijsko preslikavanje kao i kompaktnost te proučavana neka njihova svojstva.This diploma thesis is divided in three chapters. Basic notions like topology, topological space and basis of topology are defined in the first chapter. The second chapter consists of the theme of this diploma thesis, more exactly it is talking about decomposition spaces. Decomposition topology and decomposition spaces are defined here and numerous examples of such spaces are given. This chapter also speaks of Hausdorff spaces. In third, final chapter, a special case of decomposition space is analyzed, also known as quotient space, more precisely quotient of topological space and set. Decomposition map is also defined here, as well as compactness and some of their properties

Dekompozicijski prostori

Ovaj diplomski rad podijeljen je na tri poglavlja. U prvom poglavlju definirani su osnovni pojmovi kao što su topologija, topološki prostor i baza topologije. Drugo se poglavlje sastoji od same teme ovog diplomskog rada, odnosno govori o dekompozicijskim prostorima. Ovdje je definirana dekompozicijska topologija, dekompozicijski prostori te su dani mnogobrojni primjeri navedenih prostora. Također, ovdje se govori i o Hausdorffovim prostorima. U trećem, završnom poglavlju, proučavan je poseban slučaj dekompozicijskog prostora koji se naziva kvocijentni prostor, točnije kvocijent topološkog prostora i skupa. Definirano je dekompozicijsko preslikavanje kao i kompaktnost te proučavana neka njihova svojstva.This diploma thesis is divided in three chapters. Basic notions like topology, topological space and basis of topology are defined in the first chapter. The second chapter consists of the theme of this diploma thesis, more exactly it is talking about decomposition spaces. Decomposition topology and decomposition spaces are defined here and numerous examples of such spaces are given. This chapter also speaks of Hausdorff spaces. In third, final chapter, a special case of decomposition space is analyzed, also known as quotient space, more precisely quotient of topological space and set. Decomposition map is also defined here, as well as compactness and some of their properties

The HicA toxin from Burkholderia pseudomallei has a role in persister cell formation

© 2014 The Authors Journal compilation. ©2014 Biochemical Society.This is an open access article that is freely available in ORE or from the publisher's website. Please cite the published version.Published by Portland Press on behalf of the Biochemical SocietyTA (toxin-antitoxin) systems are widely distributed amongst bacteria and are associated with the formation of antibiotic tolerant (persister) cells that may have involvement in chronic and recurrent disease. We show that overexpression of the Burkholderia pseudomallei HicA toxin causes growth arrest and increases the number of persister cells tolerant to ciprofloxacin or ceftazidime. Furthermore, our data show that persistence towards ciprofloxacin or ceftazidime can be differentially modulated depending on the level of induction of HicA expression. Deleting the hicAB locus from B. pseudomallei K96243 significantly reduced persister cell frequencies following exposure to ciprofloxacin, but not ceftazidime. The structure of HicA(H24A) was solved by NMR and forms a dsRBD-like (dsRNA-binding domain-like) fold, composed of a triple-stranded β-sheet, with two helices packed against one face. The surface of the protein is highly positively charged indicative of an RNA-binding protein and His24 and Gly22 were functionality important residues. This is the first study demonstrating a role for the HicAB system in bacterial persistence and the first structure of a HicA protein that has been experimentally characterized.Wellcome Trus

Mammalian cell entry genes in Streptomyces may provide clues to the evolution of bacterial virulence

Understanding the evolution of virulence is key to appreciating the role specific loci play in pathogenicity. Streptomyces species are generally non-pathogenic soil saprophytes, yet within their genome we can find homologues of virulence loci. One example of this is the mammalian cell entry (mce) locus, which has been characterised in Mycobacterium tuberculosis. To investigate the role in Streptomyces we deleted the mce locus and studied its impact on cell survival, morphology and interaction with other soil organisms. Disruption of the mce cluster resulted in virulence towards amoebae (Acanthamoeba polyphaga) and reduced colonization of plant (Arabidopsis) models, indicating these genes may play an important role in Streptomyces survival in the environment. Our data suggest that loss of mce in Streptomyces spp. may have profound effects on survival in a competitive soil environment, and provides insight in to the evolution and selection of these genes as virulence factors in related pathogenic organisms

The Efficacy of Exercise in Reducing Depressive Symptoms among Cancer Survivors: A Meta-Analysis

INTRODUCTION: The purpose of this meta-analysis was to examine the efficacy of exercise to reduce depressive symptoms among cancer survivors. In addition, we examined the extent to which exercise dose and clinical characteristics of cancer survivors influence the relationship between exercise and reductions in depressive symptoms. METHODS: We conducted a systematic search identifying randomized controlled trials of exercise interventions among adult cancer survivors, examining depressive symptoms as an outcome. We calculated effect sizes for each study and performed weighted multiple regression moderator analysis. RESULTS: We identified 40 exercise interventions including 2,929 cancer survivors. Diverse groups of cancer survivors were examined in seven exercise interventions; breast cancer survivors were examined in 26; prostate cancer, leukemia, and lymphoma were examined in two; and colorectal cancer in one. Cancer survivors who completed an exercise intervention reduced depression more than controls, d(+) = -0.13 (95% CI: -0.26, -0.01). Increases in weekly volume of aerobic exercise reduced depressive symptoms in dose-response fashion (β = -0.24, p = 0.03), a pattern evident only in higher quality trials. Exercise reduced depressive symptoms most when exercise sessions were supervised (β = -0.26, p = 0.01) and when cancer survivors were between 47-62 yr (β = 0.27, p = 0.01). CONCLUSION: Exercise training provides a small overall reduction in depressive symptoms among cancer survivors but one that increased in dose-response fashion with weekly volume of aerobic exercise in high quality trials. Depressive symptoms were reduced to the greatest degree among breast cancer survivors, among cancer survivors aged between 47-62 yr, or when exercise sessions were supervised

Phenotypic and Genome-Wide Analysis of an Antibiotic-Resistant Small Colony Variant (SCV) of Pseudomonas aeruginosa

Small colony variants (SCVs) are slow-growing bacteria, which often show increased resistance to antibiotics and cause latent or recurrent infections. It is therefore important to understand the mechanisms at the basis of this phenotypic switch.One SCV (termed PAO-SCV) was isolated, showing high resistance to gentamicin and to the cephalosporine cefotaxime. PAO-SCV was prone to reversion as evidenced by emergence of large colonies with a frequency of 10(-5) on media without antibiotics while it was stably maintained in presence of gentamicin. PAO-SCV showed a delayed growth, defective motility, and strongly reduced levels of the quorum sensing Pseudomonas quinolone signal (PQS). Whole genome expression analysis further suggested a multi-layered antibiotic resistance mechanism, including simultaneous over-expression of two drug efflux pumps (MexAB-OprM, MexXY-OprM), the LPS modification operon arnBCADTEF, and the PhoP-PhoQ two-component system. Conversely, the genes for the synthesis of PQS were strongly down-regulated in PAO-SCV. Finally, genomic analysis revealed the presence of mutations in phoP and phoQ genes as well as in the mexZ gene encoding a repressor of the mexXY and mexAB-oprM genes. Only one mutation occurred only in REV, at nucleotide 1020 of the tufA gene, a paralog of tufB, both encoding the elongation factor Tu, causing a change of the rarely used aspartic acid codon GAU to the more common GAC, possibly causing an increase of tufA mRNA translation. High expression of phoP and phoQ was confirmed for the SCV variant while the revertant showed expression levels reduced to wild-type levels.By combining data coming from phenotypic, gene expression and proteome analysis, we could demonstrate that resistance to aminoglycosides in one SCV mutant is multifactorial including overexpression of efflux mechanisms, LPS modification and is accompanied by a drastic down-regulation of the Pseudomonas quinolone signal quorum sensing system

Quod faustum fuat || NVPTIAS DO=||CTISS. ET ORNA-||TISS. IVVENIS, DAVIDIS || SPEISERI, Sondershusini, LL. Studiosi;|| ... Dn. THEO-||DORICI SPEISERI, in inclitâ || Sondershusâ multos retrò an-||nos Schuuarzburgici || Quaestoris,|| FILII,|| Cum ... Virgine || MARIA,|| ... M. MICHAE-||LIS NEANDRI Sorauiensis; Coenobij & || Scholae Ilfeldensis ad ann. 45. Abbatis || & Rectoris digniss. p.m.|| FILIA,|| Solenni ritu Sondershusae celebratas postri-||die S. Martini,|| 1599.|| Felici hac metrica apprecatione & votis || clarare dignantur:|| Praeceptores, Affines, et Amici.||

Vorlageform des Erscheinungsvermerks: (ERPHORDIAE || Typis suis excudebat Iohan. Pistorius.||) [1599