Clinical Indicators of Bone Deterioration in Alcoholic Liver Cirrhosis and Chronic Alcohol Abuse: Looking beyond Bone Fracture Occurrence

Although previous studies indicated that chronic alcohol abuse (CAA) and alcoholic liver cirrhosis (ALC) are associated with increased bone fragility, understanding bone fragility determinants is still modest in these individuals. We used a comprehensive individualized clinical fracture risk assessment approach (vertebral osteodensitometry, femoral osteodensitometry and geometry, and serum bone turnover biomarkers) to compare adult male patients with ALC who have not previously had femoral or vertebral fractures (n = 39), patients with CAA (without liver cirrhosis, n = 78) who have not previously had femoral or vertebral fractures and healthy age- and sex-matched controls (n = 43). Our data suggested that intertrochanteric bone mineral density was significantly lower in ALC and CAA patients than in controls. Also, the trabecular bone score was considerably lower in ALC patients compared with CAA and control individuals. The most significant inter-group differences in femoral geometry were noted on the femoral shaft. Patients with ALC and CAA have a higher 10-year risk of major osteoporotic fractures compared to the controls. Analysis of bone turnover biomarkers showed increased osteoprotegerin and beta-C-terminal telopeptide serum concentrations and decreased insulin growth factor-1 concentrations in patients with ALC compared to CAA and control groups. Our data revealed that bone alterations are present in patients with ALC and CAA even if they did not sustain a nontraumatic bone fracture, but it is also indicative that current bone-assessing clinical methods are not entirely reliable. Thus, future studies should focus on developing a reliable integrative clinical tool that can be used to accurately predict and prevent bone fracture occurrences in patients with ALC and CAA.

Differences in countermovement vertical jump force-time metrics between starting and non-starting professional male basketball players

With force plates being widely implemented for neuromuscular performance assessment in sport-specific settings and various force-time metrics being able to differentiate athletes based on their performance capabilities, the purpose of the present study was to examine the differences in countermovement vertical jump (CVJ) characteristics between starting and non-starting professional male basketball players (e.g., ABA League). Twenty-three athletes (height = 199.2 ± 7.7 kg, body mass = 94.2 ± 8.2 kg, age = 23.8 ± 4.9 years) volunteered to participate in the present investigation. Upon completion of a standardized warm-up protocol, each athlete performed three maximal-effort CVJs without an arm swing while standing on a uni-axial force plate system sampling at 1,000 Hz. Independent t-tests were used to examine statistically significant differences (p < 0.05) in each force-time metric between starters (n = 10) and non-starters (n = 13). No significant differences in any of the CVJ force-time metrics of interest were observed between the two groups, during both the eccentric and concentric phases of the movement (i.e., impulse, duration, peak velocity, and mean and peak force and power). Moreover, starters and non-starters demonstrated similar performance on CVJ outcome (e.g., jump height) and strategy metrics (e.g., countermovement depth). Overall, these findings suggest that at the professional level of play, the ability to secure a spot in the starting lineup is not primarily determined by the players' CVJ performance characteristics.

TReND in Africa: Toward a Truly Global (Neuro)science Community

TReND is a volunteer-scientist run charity dedicated to promoting research and education on the African continent. Focusing on neuroscience, we discuss approaches to address some of the factors that currently stifle Africa’s scientific development and our experience in implementing them.

Genomic data provide new insights on the demographic history and the extent of recent material transfers in Norway spruce

Primeval forests are today exceedingly rare in Europe, and transfer of forest reproductive material for afforestation and improvement has been very common, especially over the last two centuries. This can be a serious impediment when inferring past population movements in response to past climate changes such as the last glacial maximum (LGM), some 18,000 years ago. In the present study, we genotyped 1,672 individuals from three Picea species (P. abies, P. obovata, and P. omorika) at 400K SNPs using exome capture to infer the past demographic history of Norway spruce (P. abies) and estimate the amount of recent introduction used to establish the Norway spruce breeding program in southern Sweden. Most of these trees belong to P. abies and originate from the base populations of the Swedish breeding program. Others originate from populations across the natural ranges of the three species. Of the 1,499 individuals stemming from the breeding program, a large proportion corresponds to recent introductions from mainland Europe. The split of P. omorika occurred 23 million years ago (mya), while the divergence between P. obovata and P. abies began 17.6 mya. Demographic inferences retrieved the same main clusters within P. abies than previous studies, that is, a vast northern domain ranging from Norway to central Russia, where the species is progressively replaced by Siberian spruce (P. obovata) and two smaller domains, an Alpine domain and a Carpathian one, but also revealed further subdivision and gene flow among clusters. The three main domains divergence was ancient (15 mya), and all three went through a bottleneck corresponding to the LGM. Approximately 17% of P. abies Nordic domain migrated from P. obovata ~103K years ago, when both species had much larger effective population sizes. Our analysis of genomewide polymorphism data thus revealed the complex demographic history of Picea genus in Western Europe and highlighted the importance of material transfer in Swedish breeding program.

Capture the vertebral fracture: Risk factors as a prediction

OBJECTIVE

Vertebral fractures are the most common osteoporotic fractures occurring due to low bone mineral density, as well as other risk factors. The aim of the paper is to investigate risk factors for vertebral osteoporotic fracture occurrence in postmenopausal women.

METHODS

Retrospective analysis of data pertaining to 651 postmenopausal women obtained from the National Osteoporosis Registry of Serbia was conducted. Further analyses were performed on 217 osteoporotic women identified from those records, whereby those in the experimental group (n= 110) had a vertebral fracture, while those assigned to the control group (n= 107) did not. The two groups were comparable in terms of age (t= 0.450; p> 0.01). Risk factors that could serve as the best predictors of vertebral fracture occurrence were investigated. Multivariate logistic regression analysis was used for testing effect of several factors on vertebral fracture occurrence as the dependent variable.

RESULTS

Patients that have never suffered a vertebral fracture had a significantly higher bone mineral density (t= 8.161; p< 0.01) in comparison to those with a verified vertebral fracture. Factors that significantly contributed to the risk of vertebral fracture were presence of kyphosis (OR 708.338; 95% CI 19.238-26.081.950), use of glucocorticoids (OR 87.618; 95% CI 9.175-836.707), and presence of comorbidities (OR 7.327; 95% CI 1.500-35.793). Moreover, a unit increase in body mass index (BMI) was found to lower the probability of vertebral fracture by a factor of 0.846. Women that entered menopause later have lower chance of suffering a vertebral fracture (OR = 0.539; 95% CI 0.400-0.726).

CONCLUSION

Lower body mass index, presence of kyphosis, use of glucocorticoids, early menopause onset, and presence of comorbidities are the factors that contribute the most to vertebral osteoporotic fracture occurrence.

Honey bee viruses in Serbian colonies of different strength

Protection of honey bees is of great economic importance because of their role in pollination. Crucial steps towards this goal are epidemiological surveys of pathogens connected with honey bee losses. In this study deformed wing virus (DWV), chronic bee paralysis virus (CBPV), acute bee paralysis virus (ABPV) and sacbrood virus (SBV) were investigated in colonies of different strength located in five regions of Serbia. The relationship between colony strength and virus occurrence/infection intensity were assessed as well as the genetic relationship between virus sequences from Serbia and worldwide. Real-time RT-PCR analyses detected at least one virus in 87.33% of colonies. Single infection was found in 28.67% colonies (21.33%, 4.00%, 2.67% and 0.67% in cases of DWV, ABPV, SBV and CBPV, respectively). In the majority of colonies (58.66%) more than one virus was found. The most prevalent was DWV (74%), followed by ABPV, SBV and CBPV (49.30%, 24.00% and 6.70%, respectively). Except for DWV, the prevalence of the remaining three viruses significantly varied between the regions. No significant differences were found between colony strength and either (i) the prevalence of DWV, ABPV, SBV, CBPV and their combinations, or (ii) DWV infection levels. The sequences of honey bee viruses obtained from bees in Serbia were 93-99% identical with those deposited in GenBank.

Mitochondrial super-haplogroup U diversity in Serbians

BACKGROUND

Available mitochondrial (mtDNA) data demonstrate genetic differentiation among South Slavs inhabiting the Balkan Peninsula. However, their resolution is insufficient to elucidate the female-specific aspects of the genetic history of South Slavs, including the genetic impact of various migrations which were rather common within the Balkans, a region having a turbulent demographic history.

AIM

The aim was to thoroughly study complete mitogenomes of Serbians, a population linking westward and eastward South Slavs.

SUBJECTS AND METHODS

Forty-six predominantly Serbian super-haplogroup U complete mitogenomes were analysed phylogenetically against ∼4000 available complete mtDNAs of modern and ancient Western Eurasians.

RESULTS

Serbians share a number of U mtDNA lineages with Southern, Eastern-Central and North-Western Europeans. Putative Balkan-specific lineages (e.g. U1a1c2, U4c1b1, U5b3j, K1a4l and K1a13a1) and lineages shared among Serbians (South Slavs) and West and East Slavs were detected (e.g. U2e1b1, U2e2a1d, U4a2a, U4a2c, U4a2g1, U4d2b and U5b1a1).

CONCLUSION

The exceptional diversity of maternal lineages found in Serbians may be associated with the genetic impact of both autochthonous pre-Slavic Balkan populations whose mtDNA gene pool was affected by migrations of various populations over time (e.g. Bronze Age pastoralists) and Slavic and Germanic newcomers in the early Middle Ages.

Stem cell function and stress response are controlled by protein synthesis

Whether protein synthesis and cellular stress response pathways interact to control stem cell function is currently unknown. Here we show that mouse skin stem cells synthesize less protein than their immediate progenitors in vivo, even when forced to proliferate. Our analyses reveal that activation of stress response pathways drives both a global reduction of protein synthesis and altered translational programmes that together promote stem cell functions and tumorigenesis. Mechanistically, we show that inhibition of post-transcriptional cytosine-5 methylation locks tumour-initiating cells in this distinct translational inhibition programme. Paradoxically, this inhibition renders stem cells hypersensitive to cytotoxic stress, as tumour regeneration after treatment with 5-fluorouracil is blocked. Thus, stem cells must revoke translation inhibition pathways to regenerate a tissue or tumour.

Neurogenomics: An opportunity to integrate neuroscience, genomics and bioinformatics research in Africa

Modern genomic approaches have made enormous contributions to improving our understanding of the function, development and evolution of the nervous system, and the diversity within and between species. However, most of these research advances have been recorded in countries with advanced scientific resources and funding support systems. On the contrary, little is known about, for example, the possible interplay between different genes, non-coding elements and environmental factors in modulating neurological diseases among populations in low-income countries, including many African countries. The unique ancestry of African populations suggests that improved inclusion of these populations in neuroscience-related genomic studies would significantly help to identify novel factors that might shape the future of neuroscience research and neurological healthcare. This perspective is strongly supported by the recent identification that diseased individuals and their kindred from specific sub-Saharan African populations lack common neurological disease-associated genetic mutations. This indicates that there may be population-specific causes of neurological diseases, necessitating further investigations into the contribution of additional, presently-unknown genomic factors. Here, we discuss how the development of neurogenomics research in Africa would help to elucidate disease-related genomic variants, and also provide a good basis to develop more effective therapies. Furthermore, neurogenomics would harness African scientists' expertise in neuroscience, genomics and bioinformatics to extend our understanding of the neural basis of behaviour, development and evolution.

An open science peer review oath

One of the foundations of the scientific method is to be able to reproduce experiments and corroborate the results of research that has been done before. However, with the increasing complexities of new technologies and techniques, coupled with the specialisation of experiments, reproducing research findings has become a growing challenge. Clearly, scientific methods must be conveyed succinctly, and with clarity and rigour, in order for research to be reproducible. Here, we propose steps to help increase the transparency of the scientific method and the reproducibility of research results: specifically, we introduce a peer-review oath and accompanying manifesto. These have been designed to offer guidelines to enable reviewers (with the minimum friction or bias) to follow and apply open science principles, and support the ideas of transparency, reproducibility and ultimately greater societal impact. Introducing the oath and manifesto at the stage of peer review will help to check that the research being published includes everything that other researchers would need to successfully repeat the work. Peer review is the lynchpin of the publishing system: encouraging the community to consciously (and conscientiously) uphold these principles should help to improve published papers, increase confidence in the reproducibility of the work and, ultimately, provide strategic benefits to authors and their institutions.

An open science peer review oath

One of the foundations of the scientific method is to be able to reproduce experiments and corroborate the results of research that has been done before. However, with the increasing complexities of new technologies and techniques, coupled with the specialisation of experiments, reproducing research findings has become a growing challenge. Clearly, scientific methods must be conveyed succinctly, and with clarity and rigour, in order for research to be reproducible. Here, we propose steps to help increase the transparency of the scientific method and the reproducibility of research results: specifically, we introduce a peer-review oath and accompanying manifesto. These have been designed to offer guidelines to enable reviewers (with the minimum friction or bias) to follow and apply open science principles, and support the ideas of transparency, reproducibility and ultimately greater societal impact. Introducing the oath and manifesto at the stage of peer review will help to check that the research being published includes everything that other researchers would need to successfully repeat the work. Peer review is the lynchpin of the publishing system: encouraging the community to consciously (and conscientiously) uphold these principles should help to improve published papers, increase confidence in the reproducibility of the work and, ultimately, provide strategic benefits to authors and their institutions.

The role of Dichaete in transcriptional regulation during Drosophila embryonic development

Background

Group B Sox domain transcription factors play conserved roles in the specification and development of the nervous system in higher metazoans. However, we know comparatively little about how these transcription factors regulate gene expression, and the analysis of Sox gene function in vertebrates is confounded by functional compensation between three closely related family members. In Drosophila, only two group B Sox genes, Dichaete and SoxN, have been shown to function during embryonic CNS development, providing a simpler system for understanding the functions of this important class of regulators.

Results

Using a combination of transcriptional profiling and genome-wide binding analysis we conservatively identify over 1000 high confidence direct Dichaete target genes in the Drosophila genome. We show that Dichaete plays key roles in CNS development, regulating aspects of the temporal transcription factor sequence that confer neuroblast identity. Dichaete also shows a complex interaction with Prospero in the pathway controlling the switch from stem cell self-renewal to neural differentiation. Dichaete potentially regulates many more genes in the Drosophila genome and was found to be associated with over 2000 mapped regulatory elements.

Conclusions

Our analysis suggests that Dichaete acts as a transcriptional hub, controlling multiple regulatory pathways during CNS development. These include a set of core CNS expressed genes that are also bound by the related Sox2 gene during mammalian CNS development. Furthermore, we identify Dichaete as one of the transcription factors involved in the neural stem cell transcriptional network, with evidence supporting the view that Dichaete is involved in controlling the temporal series of divisions regulating neuroblast identity.

Characterizing 5-methylcytosine in the mammalian epitranscriptome

The post-transcriptional modification 5-methylcytosine (m5C) occurs in a wide range of coding and non-coding RNAs. We describe transcriptome-wide approaches to capture the global m5C RNA methylome. We also discuss the potential functions of m5C in RNA and compare them to 6-methyladenosine modifications.

metabolicMine: an integrated genomics, genetics and proteomics data warehouse for common metabolic disease research

Common metabolic and endocrine diseases such as diabetes affect millions of people worldwide and have a major health impact, frequently leading to complications and mortality. In a search for better prevention and treatment, there is ongoing research into the underlying molecular and genetic bases of these complex human diseases, as well as into the links with risk factors such as obesity. Although an increasing number of relevant genomic and proteomic data sets have become available, the quantity and diversity of the data make their efficient exploitation challenging. Here, we present metabolicMine, a data warehouse with a specific focus on the genomics, genetics and proteomics of common metabolic diseases. Developed in collaboration with leading UK metabolic disease groups, metabolicMine integrates data sets from a range of experiments and model organisms alongside tools for exploring them. The current version brings together information covering genes, proteins, orthologues, interactions, gene expression, pathways, ontologies, diseases, genome-wide association studies and single nucleotide polymorphisms. Although the emphasis is on human data, key data sets from mouse and rat are included. These are complemented by interoperation with the RatMine rat genomics database, with a corresponding mouse version under development by the Mouse Genome Informatics (MGI) group. The web interface contains a number of features including keyword search, a library of Search Forms, the QueryBuilder and list analysis tools. This provides researchers with many different ways to analyse, view and flexibly export data. Programming interfaces and automatic code generation in several languages are supported, and many of the features of the web interface are available through web services. The combination of diverse data sets integrated with analysis tools and a powerful query system makes metabolicMine a valuable research resource. The web interface makes it accessible to first-time users, whereas the Application Programming Interface (API) and web services provide convenient data access and tools for bioinformaticians. metabolicMine is freely available online at http://www.metabolicmine.org Database URL: http://www.metabolicmine.org.

Identifying targets of the Sox domain protein Dichaete in the Drosophila CNS via targeted expression of dominant negative proteins

BACKGROUND

Group B Sox domain transcription factors play important roles in metazoan central nervous system development. They are, however, difficult to study as mutations often have pleiotropic effects and other Sox family members can mask phenotypes due to functional compensation. In Drosophila melanogaster, the Sox gene Dichaete is dynamically expressed in the embryonic CNS, where it is known to have functional roles in neuroblasts and the ventral midline. In this study, we use inducible dominant negative proteins in combination with ChIP, immunohistochemistry and genome-wide expression profiling to further dissect the role of Dichaete in these two tissues.

RESULTS

We generated two dominant negative Dichaete constructs, one lacking a DNA binding domain and the other fused to the Engrailed transcriptional repressor domain. We expressed these tissue-specifically in the midline and in neuroblasts using the UAS/GAL4 system, validating their use at the phenotypic level and with known target genes. Using ChIP and immunohistochemistry, we identified two new likely direct Dichaete target genes, commisureless in the midline and asense in the neuroectoderm. We performed genome-wide expression profiling in stage 8-9 embryos, identifying almost a thousand potential tissue-specific Dichaete targets, with half of these genes showing evidence of Dichaete binding in vivo. These include a number of genes with known roles in CNS development, including several components of the Notch, Wnt and EGFR signalling pathways.

CONCLUSIONS

As well as identifying commisureless as a target, our data indicate that Dichaete helps establish its expression during early midline development but has less effect on its established later expression, highlighting Dichaete action on tissue specific enhancers. An analysis of the broader range of candidate Dichaete targets indicates that Dichaete plays diverse roles in CNS development, with the 500 or so Dichaete-bound putative targets including a number of transcription factors, signalling pathway components and terminal differentiation genes. In the early neurectoderm we implicate Dichaete in the lateral inhibition pathway and show that Dichaete acts to repress the proneural gene asense. Our analysis also reveals that dominant negatives cause off-target effects, highlighting the need to use other experimental data for validating findings from dominant negative studies.

InterMine: a flexible data warehouse system for the integration and analysis of heterogeneous biological data

Summary: InterMine is an open-source data warehouse system that facilitates the building of databases with complex data integration requirements and a need for a fast customizable query facility. Using InterMine, large biological databases can be created from a range of heterogeneous data sources, and the extensible data model allows for easy integration of new data types. The analysis tools include a flexible query builder, genomic region search and a library of ‘widgets’ performing various statistical analyses. The results can be exported in many commonly used formats. InterMine is a fully extensible framework where developers can add new tools and functionality. Additionally, there is a comprehensive set of web services, for which client libraries are provided in five commonly used programming languages.

Availability: Freely available from http://www.intermine.org under the LGPL license.

Contact:g.micklem@gen.cam.ac.uk

Supplementary information:Supplementary data are available at Bioinformatics online.

Role of veterinarians in recognition and prevention of animal abuse

Since the Criminal law of the Republic of Serbia in 2005 as well as the Law on veterinary medicine, there has been an increasing number of cases that deal with raising criminal charges due to animal killing or torturing. There is also a significant number of forensic cases that are aimed at discovering criminal acts. Animal abuse is a social issue, which includes a range of behaviors of humans that are harmful to animals, starting from unintentional neglect to intentional cruelty. Types of animal abuse are different and they can include physical, sexual, emotional abuse, or neglect. Abuse and neglect of animals have a variety of forms and manifestations, but the end result is always the same - animal suffering. The connection between animal abuse, domestic violence, and child abuse indicates that there is a significant role of veterinarians in social contexts and in terms of stopping this vicious cycle by preventing, discovering and turning in suspects involved in these crimes. The help that veterinarians provide to public prosecutors is of great importance. This study shows the role of veterinarians in cases of possible animal abuse, as well as their role in processing that type of cases.

ChIPing away at the genome: the new frontier travel guide

Chromatin immunoprecipitation (ChIP) is a powerful technique for obtaining in vivo data on protein-DNA binding, providing an invaluable tool for elucidating gene regulation at a molecular level. Combined with high-throughput methods such as microarrays (ChIP-array) and second generation sequencing (ChIP-seq), the technique is now commonly used for answering questions about protein binding on a genome-wide level. This review focuses on the use of microarrays and sequencing for ChIP studies, provides a critical comparison of the currently used platforms and an overview of the computational methods available, and offers recommendations for optimal use of the techniques in a research context.

Nonsteroidal antiinflammatory drugs and risk of gastrointestinal bleeding among patients on hemodialysis

BACKGROUND

Both use of nonsteroidal antiinflammatory drugs (NSAIDs) and chronic renal insufficiency are significant independent risk factors for gastrointestinal bleeding.

OBJECTIVE

The aim of our study was to investigate whether regular use of NSAIDs further increases the risk of gastrointestinal bleeding among patients with end-stage renal insufficiency on hemodialysis.

METHODS

This was a case-control study. Case and control patients were selected from the lists of patients on hemodialysis during the period of 4 months (n=650), at 3 secondary care general hospitals in Serbia. Cases (n=33) were chosen from the study population if they had experienced at least 1 episode of gastrointestinal bleeding during the last 3 years. For each case, at least 1 sex- and age-matched control patient (n=45) was randomly selected from the source population.

RESULTS

Among patients on hemodialysis, NSAIDs users had approximately 3 times higher risk of developing gastrointestinal bleeding, than non-users (crude odds ratio = 3.29; 95% confidence interval [95% CI], 1.28-8.45). After adjustment for potential confounders (sex, age, use of erythropoietin or parenteral iron, frequency of NSAID use, smoking, drinking alcohol, heart failure, arterial hypertension, diabetes mellitus, chronic obstructive pulmonary disease, and use of anticoagulants, antiplatelet agents, beta-blockers, angiotensin-converting enzyme inhibitors or diuretics), the only significant association that remained was between gastrointestinal bleeding and use of NSAIDs (OR adjusted = 5.8; 95% CI, 1.3-26.9; p=0.024).

CONCLUSION

There is a need for development of effective strategies to prevent gastrointestinal bleeding in patients on hemodialysis who use NSAIDs.

Biases in Drosophila melanogaster protein trap screens

BACKGROUND

The ability to localise or follow endogenous proteins in real time in vivo is of tremendous utility for cell biology or systems biology studies. Protein trap screens utilise the random genomic insertion of a transposon-borne artificial reporter exon (e.g. encoding the green fluorescent protein, GFP) into an intron of an endogenous gene to generate a fluorescent fusion protein. Despite recent efforts aimed at achieving comprehensive coverage of the genes encoded in the Drosophila genome, the repertoire of genes that yield protein traps is still small.

RESULTS

We analysed the collection of available protein trap lines in Drosophila melanogaster and identified potential biases that are likely to restrict genome coverage in protein trap screens. The protein trap screens investigated here primarily used P-element vectors and thus exhibit some of the same positional biases associated with this transposon that are evident from the comprehensive Drosophila Gene Disruption Project. We further found that protein trap target genes usually exhibit broad and persistent expression during embryonic development, which is likely to facilitate better detection. In addition, we investigated the likely influence of the GFP exon on host protein structure and found that protein trap insertions have a significant bias for exon-exon boundaries that encode disordered protein regions. 38.8% of GFP insertions land in disordered protein regions compared with only 23.4% in the case of non-trapping P-element insertions landing in coding sequence introns (p < 10(-4)). Interestingly, even in cases where protein domains are predicted, protein trap insertions frequently occur in regions encoding surface exposed areas that are likely to be functionally neutral. Considering the various biases observed, we predict that less than one third of intron-containing genes are likely to be amenable to trapping by the existing methods.

CONCLUSION

Our analyses suggest that the utility of P-element vectors for protein trap screens has largely been exhausted, and that approximately 2,800 genes may still be amenable using piggyBac vectors. Thus protein trap strategies based on current approaches are unlikely to offer true genome-wide coverage. We suggest that either transposons with reduced insertion bias or recombineering-based targeting techniques will be required for comprehensive genome coverage in Drosophila.

Temperature and flow visualization in a simulation of the Czochralski process using temperature-sensitive liquid crystals

There is no doubt today that thermal and thermocapillary convection play a dominant role in momentum, heat, and mass transfer in the Czochralski crystal growth method. Because of the complexity of the problems, measurements in one point of the volume are not sufficient to illuminate the flow topography or to compare the experimental results with real or numerically simulated data. Therefore, it is of great interest to measure the temperatures and velocities in the whole field in order to qualitatively analyze thermally driven convection. The new experimental particle image thermometry method, based on computer-aided color analysis of the TLCs reported here, enables the simultaneous determination of the temperature and velocity fields.