Approaches to optimize Uzbekistan's investment in irrigation technologies

For many decades, Uzbekistan has been one of the largest cotton producers in the world. The irrigation water needed for these high production levels has been delivered by the massive diversion of the Amu Darya and Syr Darya rivers, which naturally flowed into the Aral Sea. This diversion for agriculture was the main cause of the rapid decline of the Aral Sea, which is at only 10% of its original size today. The traditional method of irrigation, which relies on simple open canal systems, is highly inefficient for managing the region’s critical and limited water resource. It has been qualitatively estimated, for example, that irrigation water lost to evaporation and system inefficiencies is quite large. With the future availability of water at risk for agriculture in Central Asia, primarily due to the loss of glacial volume from global warming, along with declines in seasonal snowpack, it is clear that new approaches to water management are needed. Any serious efforts to restore the Aral Sea and its ecological services would also reduce supplies of irrigation water for Uzbekistan. While regional conflict over water is unlikely, it must be considered since Uzbekistan is a downstream country among several that rely on the Amu Darya and Syr Darya rivers for most of their water supplies. To insure against these risks to cotton poduction and the underlying economy, better irrigation technologies are needed across Uzbekistan. However, these technologies can be quite expensive, especially given that water is still nearly free. In this case study we explore the use of real options nalysis (ROA) to look for optimal investment strategies in efficient irrigation technologies in light of variable climate and policy uncertainties

An optimum Hamiltonian for non-Hermitian quantum evolution and the complex Bloch sphere

For a quantum system governed by a non-Hermitian Hamiltonian, we studied the problem of obtaining an optimum Hamiltonian that generates nonunitary transformations of a given initial state into a certain final state in the smallest time $\tau$. The analysis is based on the relationship between the states of the two-dimensional subspace of the Hilbert space spanned by the initial and final states and the points of the two-dimensional complex Bloch sphere.Comment: 14 pages, 8 figure

A Sub-Type of Familial Pancreatic Cancer: Evidence and Implications of Loss-of-Function Polymorphisms in Indoleamine-2,3-Dioxygenase-2.

BACKGROUND: Variation in an individual\u27s genetic status can impact the development of pancreatic ductal adenocarcinoma; however, the majority of familial pancreatic cancers (FPC) cannot yet be attributed to a specific inherited mutation. We present data suggesting a correlation between loss-of-function single nucleotide polymorphisms (SNPs) in an immune regulator gene, indoleamine-2,3-dioxygenase-2 (IDO2), and an increased risk of FPC. STUDY DESIGN: Germline DNA from patients who underwent resection for pancreatic ductal adenocarcinoma (n = 79) was sequenced for the IDO2 SNPs R248W and Y359Stop. Genotypes resulting in inactivation of IDO2 (Y325X homozygous, R248W homozygous) were labeled as homozygous, and the other genotypes were grouped as wild-type or heterozygous. Genotype distributions of each SNP were analyzed for Hardy-Weinberg deviation. A genotype frequency set from the 1000 Genomes Project (n = 99) was used as a genetic control for genotype distribution comparisons. RESULTS: A significant 2-fold increase in the overall prevalence of the Y359Stop homozygous genotype compared with the expected Hardy-Weinberg equilibrium was noted (p \u3c 0.05). Familial pancreatic cancer was noted in 15 cases (19%) and comparison of the FPC cohort set to the genetic control set showed a 3-fold increase in Y359Stop homozygous rates (p = 0.054). Overall in our cohort, the homozygous genotype group was associated with increased risk of FPC (odds ratio 5.4; 95% CI 1.6 to 17.6; p \u3c 0.01). Sex, age at diagnosis, and history of tobacco use were not found to be significantly associated with FPC. CONCLUSIONS: Our preliminary data suggest a strong association between the IDO2 inactivating Y359Stop SNP and an increased risk of FPC when compared with the control group. Future studies will evaluate the value of IDO2 genotyping as a prognostic, early detection marker for pancreatic ductal adenocarcinoma and a predictive marker for novel immune checkpoint therapies

Sequence conservation and combinatorial complexity of Drosophila neural precursor cell enhancers

<p>Abstract</p> <p>Background</p> <p>The presence of highly conserved sequences within <it>cis</it>-regulatory regions can serve as a valuable starting point for elucidating the basis of enhancer function. This study focuses on regulation of gene expression during the early events of <it>Drosophila </it>neural development. We describe the use of <it>EvoPrinter </it>and <it>cis</it>-Decoder, a suite of interrelated phylogenetic footprinting and alignment programs, to characterize highly conserved sequences that are shared among co-regulating enhancers.</p> <p>Results</p> <p>Analysis of <it>in vivo </it>characterized enhancers that drive neural precursor gene expression has revealed that they contain clusters of highly conserved sequence blocks (CSBs) made up of shorter shared sequence elements which are present in different combinations and orientations within the different co-regulating enhancers; these elements contain either known consensus transcription factor binding sites or consist of novel sequences that have not been functionally characterized. The CSBs of co-regulated enhancers share a large number of sequence elements, suggesting that a diverse repertoire of transcription factors may interact in a highly combinatorial fashion to coordinately regulate gene expression. We have used information gained from our comparative analysis to discover an enhancer that directs expression of the <it>nervy </it>gene in neural precursor cells of the CNS and PNS.</p> <p>Conclusion</p> <p>The combined use <it>EvoPrinter </it>and <it>cis</it>-Decoder has yielded important insights into the combinatorial appearance of fundamental sequence elements required for neural enhancer function. Each of the 30 enhancers examined conformed to a pattern of highly conserved blocks of sequences containing shared constituent elements. These data establish a basis for further analysis and understanding of neural enhancer function.</p

Thrombospondin-3 augments injury-induced cardiomyopathy by intracellular integrin inhibition and sarcolemmal instability.

Thrombospondins (Thbs) are a family of five secreted matricellular glycoproteins in vertebrates that broadly affect cell-matrix interaction. While Thbs4 is known to protect striated muscle from disease by enhancing sarcolemmal stability through increased integrin and dystroglycan attachment complexes, here we show that Thbs3 antithetically promotes sarcolemmal destabilization by reducing integrin function, augmenting disease-induced decompensation. Deletion of Thbs3 in mice enhances integrin membrane expression and membrane stability, protecting the heart from disease stimuli. Transgene-mediated overexpression of α7β1D integrin in the heart ameliorates the disease predisposing effects of Thbs3 by augmenting sarcolemmal stability. Mechanistically, we show that mutating Thbs3 to contain the conserved RGD integrin binding domain normally found in Thbs4 and Thbs5 now rescues the defective expression of integrins on the sarcolemma. Thus, Thbs proteins mediate the intracellular processing of integrin plasma membrane attachment complexes to regulate the dynamics of cellular remodeling and membrane stability

Bath Transfers in Older Adult Congregate Housing Residents: Assessing the Person–Environment Interaction

To examine environmental feature utilization (EFU) and the types and prevalence of performance difficulties during a videotaped bath transfer and to determine the personal characteristics associated with total EFU and performance difficulties. DESIGN : Cross-sectional analysis. SETTING : Two congregate housing facilities in southeastern Michigan. PARTICIPANTS : Eighty-nine older adults who reported independence in bathing. MEASUREMENTS : Trained video coders recorded EFU (defined as upper extremity contact with features in the environment) and rated performance difficulties (defined as lack of fluid movement or difficulty negotiating the environment). EFU was measured by determining whether features used were safe (i.e., designed for use as a transfer support) or unsafe and by total EFU (i.e., number of environmental features used during the transfer). Personal characteristics included self-reported medical conditions, bath transfer difficulty, functional mobility, lower extremity strength, range of motion functional impairment, and falls efficacy. RESULTS : For participants with a tub-shower, safe EFU was higher than unsafe EFU (85% vs 19%; P <.001). Participants with shower stalls had the same rate of safe and unsafe EFU (71%). In multiple regression analysis, self-reported bath transfer difficulty was associated with total EFU ( P =.01). One-third of the sample had performance difficulties. In multivariate analysis, range of motion functional impairment (odds ratio (OR)=13.49, 95% confidence interval (CI)=1.11–163.53) and lowest quartile in falls efficacy scores (OR=5.81, 95% CI=1.24–27.41) were associated with performance difficulties. CONCLUSION : Unsafe EFU and performance difficulties were common in independently bathing older adults. Self-reported bath transfer difficulty appears to be a good indicator of high total EFU and may be used as a screening question for clinicians. Important strategies to reduce unsafe EFU and to increase falls efficacy include removing shower sliding glass doors and training older adults in safe transfer techniques.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65856/1/j.1532-5415.2006.00814.x.pd

Chaotic wave functions and exponential convergence of low-lying energy eigenvalues

We suggest that low-lying eigenvalues of realistic quantum many-body hamiltonians, given, as in the nuclear shell model, by large matrices, can be calculated, instead of the full diagonalization, by the diagonalization of small truncated matrices with the exponential extrapolation of the results. We show numerical data confirming this conjecture. We argue that the exponential convergence in an appropriate basis may be a generic feature of complicated ("chaotic") systems where the wave functions are localized in this basis.Comment: 4 figure

Home sick: impacts of migratory beekeeping on honey bee (Apis mellifera) pests, pathogens, and colony size

Honey bees are important pollinators of agricultural crops and the dramatic losses of honey bee colonies have risen to a level of international concern. Potential contributors to such losses include pesticide exposure, lack of floral resources and parasites and pathogens. The damaging effects of all of these may be exacerbated by apicultural practices. To meet the pollination demand of US crops, bees are transported to areas of high pollination demand throughout the year. Compared to stationary colonies, risk of parasitism and infectious disease may be greater for migratory bees than those that remain in a single location, although this has not been experimentally established. Here, we conducted a manipulative experiment to test whether viral pathogen and parasite loads increase as a result of colonies being transported for pollination of a major US crop, California almonds. We also tested if they subsequently transmit those diseases to stationary colonies upon return to their home apiaries. Colonies started with equivalent numbers of bees, however migratory colonies returned with fewer bees compared to stationary colonies and this difference remained one month later. Migratory colonies returned with higher black queen cell virus loads than stationary colonies, but loads were similar between groups one month later. Colonies exposed to migratory bees experienced a greater increase of deformed wing virus prevalence and load compared to the isolated group. The three groups had similar infestations of Varroa mites upon return of the migratory colonies. However, one month later, mite loads in migratory colonies were significantly lower compared to the other groups, possibly because of lower number of host bees. Our study demonstrates that migratory pollination practices has varying health effects for honey bee colonies. Further research is necessary to clarify how migratory pollination practices influence the disease dynamics of honey bee diseases we describe here