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Introduction An integral diagnosis of population contemplates within its components the population demographic analysis that is indispensable in the formulation of public policies. Population policy has a clearly transversal nature, since all actions in the economic, social, political, cultural, geographical, and obviously, demographic fields, have direct or indirect repercussions on it. Objectives To determine the population dynamics and the global growth of the older adult population (OAP) of 60 years and more. Materials and methods Cross-sectional, retrospective study. The information was obtained from the statistical yearbooks of the institute of security and social services of state workers, Mexico (1999-2015). Several demographic ageing indicators were analyzed. Results There was a constant increase in percentage points in the proportion of OAP, index of ageing, demographic dependency ratio of old age, global index of dependence, index of dependence of old people, and index of the active population structure (6, 19.2, 15.5, 8.5, 8.2 and 31.2%, respectively). The indicator global index of dependence and masculinity showed a decrease (0.6 and 3.1%, respectively). Conclusions Our data provide evidence that suggests modifying and generating public policies according to OAP.

Shell structures carry loads with their thin yet curved shapes. Being thin means shells require little material, which is desirable for minimizing embodied carbon footprints. However, the feature of being curved implies shells require immense effort to design and fabricate. To address the challenges, this dissertation consists of three parts: developing a design algorithm based on radial basis functions (RBFs), inventing a fabrication technique based on reconfigurable mechanisms, and producing prototypes based on the new algorithm and mechanism. The first part of this dissertation introduces a new algorithm based on RBFs for designing smooth membrane shells, which is more versatile than existing methods. The algorithm can generate membranes with both tensile and compressive stresses. It can also tweak an initial shape to meet free-edge conditions. It can also incorporate horizontal loads in the form-finding process. The second part of the dissertation presents a new system of flat-to-curved mechanisms, which allows a shell to be fabricated in a flat configuration and deployed into a double-curved state. Such a mechanism consists of panels connected by tilted hinges. The mechanism can contract non-homogeneously and change its Gaussian curvature. The last part of this dissertation demonstrates the integral application of the RBFs form-finding algorithm and the flat-to-curved mechanisms. The prototypes designed and produced deliver form-found shapes that have spans ranging from 0.2 to 4 meters. This dissertation contributes to the development and distribution of shell structures by developing computer algorithms and digital fabrication techniques to minimize the hurdles of designing and fabricating shell structures.

Hybrid perovskite-based optoelectronic devices are demonstrating unprecedented growth in performance, and defect passivation approaches are highly promising routes to further improve properties. Here, the effect of the molecular ion BF4-, introduced via methylammonium tetrafluoroborate (MABF4) in a surface treatment for MAPbI3 perovskite is reported. The optical spectroscopic characterisations shows that the introduction of tetrafluoroborate leads to reduced non-radiative charge carrier recombination with a reduction in first order recombination rate from 6.5 × 106 to 2.5 × 105 s-1 in BF4--treated samples, and a consequent increase in photoluminescence quantum yield by an order of magnitude (from 0.5% to 10.4%). 19F, 11B and 14N solid-state NMR is used to elucidate the atomic-level mechanism of the BF4- additive-induced improvements, revealing that the BF4- acts as a scavenger of excess MAI by forming MAI–MABF4 cocrystals. This shifts the equilibrium of iodide concentration in the perovskite phase is presumably due to the formation of MAI-MABF4 cocrystal, thereby reducing the concentration of interstitial iodide defects that act as deep traps and non-radiative recombination centers. These collective results allow us, for the first time, to elucidate the microscopic mechanism of action of BF4-.

This paper extends polyhedral Airy stress functions to incorporate body forces. Stresses of an equilibrium state of a 2D structure can be represented by the sec- ond derivatives of a smooth Airy stress function and the integrals of body forces. In the absence of body forces, a smooth Airy stress function can be discretised into a polyhedron as the corresponding structure is discretised into a truss. The differ- ence in slope across a creases represents the axial force on the bar, while the zero curvatures of the planar faces represent zero stresses voids of the structure. When body forces are present, the zero-stress condition requires the discretised Airy stress function to curve with the integrals of these body forces. Meanwhile, the isotropic angles on the creases still indicate concentrated axial forces. This paper discretises the integrals of body forces into step-wise functions, and discretises the Airy stress function into quadric faces connected by curved creases. The proposed method could provide structural designers (e.g. architects, structural engineers) with a more intuitive way to perceive stress fields.

Plasma-derived polyclonal antibodies are polyvalent drugs used for many important clinical indications that require modulation of multiple drug targets simultaneously, including emerging infectious disease and transplantation. However, plasma-derived drugs suffer many problems, including low potency, impurities, constraints on supply, and batch-to-batch variation. In this study, we demonstrated proofs-of-concept for a technology that uses microfluidics and molecular genomics to capture diverse mammalian antibody repertoires as multivalent recombinant drugs. These “recombinant hyperimmune” drugs comprised thousands to tens of thousands of antibodies and were derived from convalescent human donors, or vaccinated human donors or immunized mice. Here we used our technology to build a highly potent recombinant hyperimmune for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS CoV-2) in less than three months. We also validated a recombinant hyperimmune for Zika virus disease that abrogates antibody-dependent enhancement (ADE) through Fc engineering. For patients with primary immune deficiency (PID), we built high potency polyvalent recombinant hyperimmunes against pathogens that commonly cause serious lung infections. Finally, to address the limitations of rabbit-derived anti-thymocyte globulin (ATG), we generated a recombinant human version and demonstrated in vivo function against graft-versus-host disease (GVHD). Recombinant hyperimmunes are a novel class of drugs that could be used to target a wide variety of other clinical applications, including cancer and autoimmunity.

Background. The incidence of herpes zoster is up to 9 times higher in immunosuppressed solid organ transplant recipients than in the general population. We investigated the immunogenicity and safety of an adjuvanted recombinant zoster vaccine (RZV) in renal transplant (RT) recipients ≥18 years of age receiving daily immunosuppressive therapy. Methods. In this phase 3, randomized (1:1), observer-blind, multicenter trial, RT recipients were enrolled and received 2 doses of RZV or placebo 1-2 months (M) apart 4-18M posttransplant. Anti-glycoprotein E (gE) antibody concentrations, gE-specific CD4 T-cell frequencies, and vaccine response rates were assessed at 1M post-dose 1, and 1M and 12M post-dose 2. Solicited and unsolicited adverse events (AEs) were recorded for 7 and 30 days after each dose, respectively. Solicited general symptoms and unsolicited AEs were also collected 7 days before first vaccination. Serious AEs (including biopsy-proven allograft rejections) and potential immune-mediated diseases (pIMDs) were recorded up to 12M post-dose 2. Results. Two hundred sixty-four participants (RZV: 132; placebo: 132) were enrolled between March 2014 and April 2017. gE-specific humoral and cell-mediated immune responses were higher in RZV than placebo recipients across postvaccination time points and persisted above prevaccination baseline 12M post-dose 2. Local AEs were reported more frequently by RZV than placebo recipients. Overall occurrences of renal function changes, rejections, unsolicited AEs, serious AEs, and pIMDs were similar between groups. Conclusions. RZV was immunogenic in chronically immunosuppressed RT recipients. Immunogenicity persisted through 12M postvaccination. No safety concerns arose. © The Author(s) 2019.

Membrane-embedded pyrophosphatase (M-PPase) hydrolyzes pyrophosphate to drive ion (H+ and/or Na+) translocation. We determined crystal structures and functions of Vigna radiata M-PPase (VrH+-PPase), the VrH+-PPase–2Pi complex and mutants at hydrophobic gate (residue L555) and exit channel (residues T228 and E225). Ion pore diameters along the translocation pathway of three VrH+-PPases complexes (Pi-, 2Pi- and imidodiphosphate-bound states) present a unique wave-like profile, with different pore diameters at the hydrophobic gate and exit channel, indicating that the ligands induced pore size alterations. The 2Pi-bound state with the largest pore diameter might mimic the hydrophobic gate open. In mutant structures, ordered waters detected at the hydrophobic gate among VrH+-PPase imply the possibility of solvation, and numerous waters at the exit channel might signify an open channel. A salt-bridge, E225–R562 is at the way out of the exit channel of VrH+-PPase; E225A mutant makes the interaction eliminated and reveals a decreased pumping ability. E225–R562 might act as a latch to regulate proton release. A water wire from the ion gate (R-D-K-E) through the hydrophobic gate and into the exit channel may reflect the path of proton transfer.

espanolIntroduccion: Un diagnostico integral de poblacion contempla dentro de sus componentes el analisis demografico poblacional, que es indispensable en la formulacion de las politicas publicas. La politica de poblacion tiene una naturaleza claramente transversal, pues todas las acciones en los ambitos economico, social, politico, cultural, geografico, y obviamente, el demografico, repercuten de una manera directa o indirecta en ella. Objetivos: Determinar la dinamica poblacional y el crecimiento global de la poblacion adulta mayor (PAM) de 60 anos y mas. Materiales y metodos: Estudio transversal, retrospectivo. La informacion se obtuvo de los anuarios estadisticos institucionales del Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Mexico (de 1999-2015). Se analizaron varios indicadores demograficos de envejecimientoDE). Resultados: Se observo un incremento constante en puntos porcentuales en la proporcion de PAM, el indice de envejecimiento, la razon de dependencia demografica de la vejez, indice global de dependencia, indice dependencia de viejos e indice de estructura de la poblacion activa (6, 19.2, 15.5, 8.5, 8.2 y 31.2%, respectivamente). El indicador global de ancianidad y el indice de masculinidad mostraron una disminucion (0.6 y 3.1%, respectivamente). Conclusiones: Nuestros datos aportan evidencia que sugiere modificar y generar politicas publicas acordes a la PAM. EnglishIntroduction: An integral diagnosis of population contemplates within its components the population demographic analysis that is indispensable in the formulation of public policies. Population policy has a clearly transversal nature, since all actions in the economic, social, political, cultural, geographical, and obviously, demographic fields, have direct or indirect repercussions on it. Objectives: To determine the population dynamics and the global growth of the older adult population (OAP) of 60 years and more. Materials and methods: Cross-sectional, retrospective study. The information was obtained from the statistical yearbooks of the institute of security and social services of state workers, Mexico (1999-2015). Several demographic ageing indicators were analyzed. Results: There was a constant increase in percentage points in the proportion of OAP, index of ageing, demographic dependency ratio of old age, global index of dependence, index of dependence of old people, and index of the active population structure (6, 19.2, 15.5, 8.5, 8.2 and 31.2%, respectively). The indicator global index of dependence and masculinity showed a decrease (0.6 and 3.1%, respectively). Conclusions: Our data provide evidence that suggests modifying and generating public policies according to OAP.

Advances in architectural geometry make free-form architecture explicitly definable and economically manufacturable. Enhancing the efficiency of fabrication, this research investigates strategies of translating free-form synclastic surfaces to flat pre-programmed reconfigurable mechanisms. The presented bi-stable mechanisms are produced by creating voids on flat materials. In such mechanisms, the generated blocks are outlined by the voids that are connected by the hinges. The position and the orientation of the hinges allow the blocks to rotate around each other, and then reconfigure from flat to synclastic. During the reconfiguration process, the blocks are temporarily deformed. As the elasticity brings the blocks back to the original dimensions, the materials reach the second stable states. Distribution of hinges on the flattened surface needs to be designed according to certain geometric constraints. This paper demonstrates the workflow of identifying the positions of the hinges. The developed methods are validated through prototypes such as a spherical surface and a free-form synclastic surface.

Solar energy has the potential to play a central role in the future global energy system because of the scale of the solar resource, its predictability, and its ubiquitous nature. Global installed solar photovoltaic (PV) capacity exceeded 500 GW at the end of 2018, and an estimated additional 500 GW of PV capacity is projected to be installed by 2022–2023, bringing us into the era of TW-scale PV. Given the speed of change in the PV industry, both in terms of continued dramatic cost decreases and manufacturing-scale increases, the growth toward TWscale PV has caught many observers, including many of us, by surprise. Two years ago, we focused on the challenges of achieving 3 to 10 TW of PV by 2030. Here, we envision a future with ~10 TW of PV by 2030 and 30 to 70 TW by 2050, providing a majority of global energy. PV would be not just a key contributor to electricity generation but also a central contributor to all segments of the global energy system. We discuss ramifications and challenges for complementary technologies (e.g., energy storage, power to gas/liquid fuels/chemicals, grid integration, and multiple sector electrification) and summarize what is needed in research in PV performance, reliability, manufacturing, and recycling.

Membrane shells, which have minimized bending moments under certain load conditions, are regarded as ideal structural forms in terms of material efficiency. Most of the existing numerical form-finding methods are based on discretizing membranes into finite panels or funicular networks and focusing on gravitational loading only. In order to obtain smooth shells and to consider horizontal loads, this paper presents a method to find the equilibrium forms of the membrane shells by solving Pucher’s equation. Radial base functions (RBFs) is utilized to represent stresses and shapes of the membranes, and a least square method is applied to find the controlling coefficients which allow the functions to fit the boundary conditions (e.g. zero stresses at the free edges) and the governing equation. When all the parameters are carefully chosen, the stress and shape functions can achieve sufficient accuracy. The presented method has been preliminarily implemented to find shells on a triangle ground plan incorporating horizontal loads. The form-found geometries are then analyzed by finite element models. The result confirms that the form-found shells have the stress distributions similar to the prescribed stresses.

Solar energy has the potential to play a central role in the future global energy system because of the scale of the solar resource, its predictability, and its ubiquitous nature. Global installed solar photovoltaic (PV) capacity exceeded 500 GW at the end of 2018, and an estimated additional 500 GW of PV capacity is projected to be installed by 2022-2023, bringing us into the era of TW-scale PV. Given the speed of change in the PV industry, both in terms of continued dramatic cost decreases and manufacturing-scale increases, the growth toward TW-scale PV has caught many observers, including many of us, by surprise. Two years ago, we focused on the challenges of achieving 3 to 10 TW of PV by 2030. Here, we envision a future with ∼10 TW of PV by 2030 and 30 to 70 TW by 2050, providing a majority of global energy. PV would be not just a key contributor to electricity generation but also a central contributor to all segments of the global energy system. We discuss ramifications and challenges for complementary technologies (e.g., energy storage, power to gas/liquid fuels/chemicals, grid integration, and multiple sector electrification) and summarize what is needed in research in PV performance, reliability, manufacturing, and recycling.

Estimation of surface reflectance is essential for an accurate retrieval of aerosol optical thickness (AOT) by satellite remote sensing approach. Due to the variability of surface reflectance over land surfaces, a surface model is required to take into account the crucial factor controlling this variability. In the present study, we attempted to simulate surface reflectance in the short-wave channels with two methods, namely the land cover type dependent method and a two-source linear model. In the two-source linear model, we assumed that the spectral property can be described by a mixture of vegetated and non-vegetated area, and both the normalized difference vegetation index (NDVI), and the vegetation continuous field (VCF) was applied to summarize this surface characteristic. By comparing our estimation with surface reflectance data derived from Moderate Resolution Imaging Spectroradiometer (MODIS), it indicated that the land cover type approach did not provide a better estimation because of inhomogeneous land cover pattern and the mixing pixel properties. For the two-source linear method, the study suggested that the use of NDVI as parameterization for vegetation fraction can reflect the spectral behavior of shortwave surface reflectance, despite of some deviation due to the averaging characteristics in our linear combination process. A channel-dependent offset and scalar factor could enhance reflectance estimation and further improve AOT retrieval by the current Bremen AErosol Retrieval (BAER) approach.

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Shell structures achieve stability through double curvature, which brings about construction challenges. This paper presents a strategy to design and assemble a panelized shell with a bi-stable mechanism aiming to make the assembly process more efficient. The developed prototype has two states of flat and three-dimensional stable configuration. This reconfiguration is achieved by reconfiguring the flattened surface of a shell into a three-dimensional structure using embedded bi-stable joints. In order to apply this approach on free-form double curved shells, a workflow to translate a shell into its flattened state is developed. Discrete components are connected using bi-stable joints, where each joint has two stable states. Once the joints are mechanically activated, they guide the adjacent components contracting and rotating into the three-dimensional configuration. Initial explorations indicate that an edge of a shell will turn into an isosceles trapezoid in the flattened configuration while a node of a conical mesh will turn into a cyclic quadrilateral in the flattened configuration. The flattening process is demonstrated using a free-form vault, while scaled physical porotypes are 3D printed with PLA and tested. Future studies require exploration into applications with construction materials at larger scales.

Unter Ausnutzung der Gewährung eines Vorsteuerabzugs im zwischenunternehmerischen Handel eröffnet das geltende Mehrwertsteuersystem eine stark zunehmende Missbrauchsmöglichkeit und führt damit in Deutschland und Taiwan zu vielfältigen Erscheinungsformen des Umsatzsteuerbetrugs. Vor diesem Hintergrund untersucht die Arbeit aus Sicht der Rechtsvergleichung eingehend, welche Varianten des Umsatzsteuerbetrugs in den beiden Ländern zu beobachten sind und welche repressiven Maßnahmen, namentlich Verwaltungssanktionen und Kriminalstrafen, im Hinblick darauf jeweils geeignet und verhältnismäßig sind. Ein Schwerpunkt liegt hierbei auf dem Zusammenspiel der umsatzsteuerlichen Tatbestände mit steuerlichen Sanktionsvorschriften und der Abstimmung von Steuerstraf- und Steuerordnungswidrigkeitsvorschriften. Schließlich mündet die Untersuchung in rechtspolitischen Empfehlungen an die Gesetzgeber beider Länder.

This pilot study attempted to reduce resistance-to-care (RTC) and combative behaviors in nursing home residents with dementia by eliciting their positive affect. Four female residents with dementia were recruited from a nursing facility. Each resident was involved in one intervention trial and one control trial. The response of the residents was assessed by the Agitated Behavior Scale and the Observational Measurement of Engagement Tool. The distress level of the certified nursing assistants (CNAs) delivering the care was reported through the Distress Thermometer. Results showed that the residents displayed fewer behavioral symptoms in the intervention trial than in the control trial. The CNAs reported less distress in the intervention trial than in the control trial. These preliminary findings suggest that it might be feasible to use positive images to reduce residents' behavioral symptoms and decrease the distress of CNAs.

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Cytokinins are N6-substituted adenine derivatives that play diverse roles in plant growth and development. We sought to define a robust set of genes regulated by cytokinin as well as to query the response of genes not represented on microarrays. To this end, we performed a meta-analysis of microarray data from a variety of cytokinin-treated samples and used RNA-seq to examine cytokinin-regulated gene expression in Arabidopsis (Arabidopsis thaliana). Microarray meta-analysis using 13 microarray experiments combined with empirically defined filtering criteria identified a set of 226 genes differentially regulated by cytokinin, a subset of which has previously been validated by other methods. RNA-seq validated about 73% of the up-regulated genes identified by this meta-analysis. In silico promoter analysis indicated an overrepresentation of type-B Arabidopsis response regulator binding elements, consistent with the role of type-B Arabidopsis response regulators as primary mediators of cytokinin-responsive gene expression. RNA-seq analysis identified 73 cytokinin-regulated genes that were not represented on the ATH1 microarray. Representative genes were verified using quantitative reverse transcription-polymerase chain reaction and NanoString analysis. Analysis of the genes identified reveals a substantial effect of cytokinin on genes encoding proteins involved in secondary metabolism, particularly those acting in flavonoid and phenylpropanoid biosynthesis, as well as in the regulation of redox state of the cell, particularly a set of glutaredoxin genes. Novel splicing events were found in members of some gene families that are known to play a role in cytokinin signaling or metabolism. The genes identified in this analysis represent a robust set of cytokinin-responsive genes that are useful in the analysis of cytokinin function in plants.

Cytokinins play critical roles in plant growth and development, with the transcriptional response to cytokinin being mediated by the type-B response regulators. In Arabidopsis (Arabidopsis thaliana), type-B response regulators (ARABIDOPSIS RESPONSE REGULATORS [ARRs]) form three subfamilies based on phylogenic analysis, with subfamily 1 having seven members and subfamilies 2 and 3 each having two members. Cytokinin responses are predominantly mediated by subfamily 1 members, with cytokinin-mediated effects on root growth and root meristem size correlating with type-B ARR expression levels. To determine which type-B ARRs can functionally substitute for the subfamily 1 members ARR1 or ARR12, we expressed different type-B ARRs from the ARR1 promoter and assayed their ability to rescue arr1 arr12 double mutant phenotypes. ARR1, as well as a subset of other subfamily 1 type-B ARRs, restore the cytokinin sensitivity to arr1 arr12. Expression of ARR10 from the ARR1 promoter results in cytokinin hypersensitivity and enhances shoot regeneration from callus tissue, correlating with enhanced stability of the ARR10 protein compared with the ARR1 protein. Examination of transfer DNA insertion mutants in subfamilies 2 and 3 revealed little effect on several well-characterized cytokinin responses. However, a member of subfamily 2, ARR21, restores cytokinin sensitivity to arr1 arr12 roots when expressed from the ARR1 promoter, indicating functional conservation of this divergent family member. Our results indicate that the type-B ARRs have diverged in function, such that some, but not all, can complement the arr1 arr12 mutant. In addition, our results indicate that type-B ARR expression profiles in the plant, along with posttranscriptional regulation, play significant roles in modulating their contribution to cytokinin signaling.

Cytokinins are plant hormones that play critical roles in growth and development. In Arabidopsis, the transcriptional response to cytokinin is regulated by action of type-B Arabidopsis response regulators (ARRs). Although central elements in the cytokinin signal transduction pathway have been identified, mechanisms controlling output remain to be elucidated. Here we demonstrate that a family of F-box proteins, called the KISS ME DEADLY (KMD) family, targets type-B ARR proteins for degradation. KMD proteins form an S-PHASE KINASE-ASSOCIATED PROTEIN1 (SKP1)/Cullin/F-box protein (SCF) E3 ubiquitin ligase complex and directly interact with type-B ARR proteins. Loss-of-function KMD mutants stabilize type-B ARRs and exhibit an enhanced cytokinin response. In contrast, plants with elevated KMD expression destabilize type-B ARR proteins leading to cytokinin insensitivity. Our results support a model in which an SCFKMD complex negatively regulates cytokinin responses by controlling levels of a key family of transcription factors.

T cell-dependent (TD) germinal center (GC) and antibody responses require coordinated interactions of T cells with B cells and antigen-presenting dendritic cells (DCs). Although B7 and CD40 costimulatory pathways are critical for these responses, a comprehensive analysis of cell type-specific pathways has been hindered by the absence of models for conditional expression of B7 or CD40. Here we report generation of conditional knockout mice for both B7 and CD40, and the use of these lines together with conditional MHC class II (MHCII) knockouts and bone marrow chimeric strategies, to analyze pathways involved in TD GC and antibody responses. Our results indicate that MHCII-restricted recognition of both DCs and B cells is necessary for generation of antigen-specific TFH cells, GC B cells, and antibody response. Notably, the requirements for expression of B7 and CD40 were distinct, with B7 expression required on DCs but not on B cells, while CD40 was required on B cells but not DCs for generation of TFH cells, antigen-specific GC B cells, and antigen-specific class-switched antibody responses. These findings identify requirements for cell and costimulatory interactions in TD GC and antibody responses and support a unique model in which major costimulatory pathways function through interaction of T cells with distinct cell populations.

Chloroplasts develop from proplastids in a process that requires the interplay of nuclear and chloroplast genomes, but key steps in this developmental process have yet to be elucidated. Here, we show that the nucleus-localized transcription factors GATA NITRATE-INDUCIBLE CARBON-METABOLISM-INVOLVED (GNC) and CYTOKININ-RESPONSIVE GATA1 (CGA1) regulate chloroplast development, growth, and division in Arabidopsis (Arabidopsis thaliana). GNC and CGA1 are highly expressed in green tissues, and the phytohormone cytokinin regulates their expression. A gnc cga1 mutant exhibits a reduction in overall chlorophyll levels as well as in chloroplast size in the hypocotyl. Ectopic overexpression of either GNC or CGA1 promotes chloroplast biogenesis in hypocotyl cortex and root pericycle cells, based on increases in the number and size of the chloroplasts, and also results in expanded zones of chloroplast production into the epidermis of hypocotyls and cotyledons and into the cortex of roots. Ectopic overexpression also promotes the development of etioplasts from proplastids in dark-grown seedlings, subsequently enhancing the deetiolation process. Inducible expression of GNC demonstrates that GNC-mediated chloroplast biogenesis can be regulated postembryonically, notably so for chloroplast production in cotyledon epidermal cells. Analysis of the gnc cga1 loss-of-function and overexpression lines supports a role for these transcription factors in regulating the effects of cytokinin on chloroplast division. These data support a model in which GNC and CGA1 serve as two of the master transcriptional regulators of chloroplast biogenesis, acting downstream of cytokinin and mediating the development of chloroplasts from proplastids and enhancing chloroplast growth and division in specific tissues.

Phylogenetic analyses of Microstegium (Andropogoneae, Poaceae) and some other Andropogoneae species were conducted inferred from the ITS/5.8S sequences. As a result of this study, Microstegium is polyphyletic. There are two rather distant monophyletic clades, one with Microstegium nudum (type of Leptatherum), M. japonicum and M. somae, the other one with M. ciliatum, M. fauriei, M. geniculatum and M. vimineum (type of Microstegium). Therefore we feel justified to reinstate the genus Leptatherum and three new combinations, Leptatherum boreale, L. nudum and L. somae, are proposed.

This paper offers a new and complete description of subnormal solutions of certain non-homogeneous second order periodic linear differential equations first studied by Gundersen and Steinbart in 1994. We have established a previously unknown relation that the general solutions (\textit{i.e.}, whether subnormal or not) of the DEs can be solved explicitly in terms of classical special functions, namely the Bessel, Lommel and Struve functions, which are important because of their numerous physical applications. In particular, we show that the subnormal solutions are written explicitly in terms of the degenerate Lommel functions $S_{\mu, \nu}(\zeta)$ and several classical special polynomials related to the Bessel functions. In fact, we solve an equivalent problem in special functions that each branch of the Lommel function $S_{\mu, \nu}(\zeta)$ degenerates if and only if $S_{\mu, \nu}({\rm e}^z)$ has finite order of growth in $\mathbf{C}$. We achieve this goal by proving new properties and identities for these functions. A number of semi-classical quantization-type results are obtained as consequences. Thus our results not only recover and extend the result of Gundersen and Steinbart \cite{GS94}, but the new identities and properties found for the Lommel functions are of independent interest in a wider context., Comment: Accepted by Crelle's journal. References updated, made various minor changes according to the final "proof"

The type B Arabidopsis Response Regulators (ARRs) of Arabidopsis thaliana are transcription factors that act as positive regulators in the two-component cytokinin signaling pathway. We employed a mutant-based approach to perform a detailed characterization of the roles of ARR1, ARR10, and ARR12 in plant growth and development. The most pronounced phenotype was found in the arr1-3 arr10-5 arr12-1 triple loss-of-function mutant, which showed almost complete insensitivity to high levels of exogenously applied cytokinins. The triple mutant exhibited reduced stature due to decreased cell division in the shoot, enhanced seed size, increased sensitivity to light, altered chlorophyll and anthocyanin concentrations, and an aborted primary root with protoxylem but no metaxylem. Microarray analysis revealed that expression of the majority of cytokinin-regulated genes requires the function of ARR1, ARR10, and ARR12. Characterization of double mutants revealed differing contributions of the type B ARRs to mutant phenotypes. Our results support a model in which cytokinin regulates a wide array of downstream responses through the action of a multistep phosphorelay that culminates in transcriptional regulation by ARR1, ARR10, and ARR12.

The generation and control of manganese sulphide particle size distribution using various mixing configurations were investigated. Specifically, this paper discusses how varying mixing intensities on a macro and micro scale affect the resultant manganese sulphide particle size distribution (PSD) at a constant concentration. The mixing variations were achieved using various Y- and T-mixers as premixing devices into a jacketed, agitated vessel. The reagents used to generate the seeds were aqueous manganese sulphate and sodium sulphide solutions. The results showed that the absence of micromixing resulted in very poor control of the particle size distribution, the particle size and the number of particles produced. This was due to the fact that the macromixing time is much greater than the corresponding precipitation time, resulting in different mixing regions existing within the reactor. From the micromixing experiments, the T–mixer was found to be the most effective mixing device at lower concentrations due to the T-mixer providing a faster mixing time than the other mixing configurations, thereby effectively localizing the supersaturation and hence controlling the precipitation. The results obtained from the direct addition without the extension pipe (i.e. short mixing time) indicated a general increase in mean particle size and decrease in total particle number at reagent concentration of 0.007 mol.dm-3 as compared to the corresponding micromixing experiments. The phenomenon may be due to incomplete crystallization at the immediate exit of the mixing device. Further experiments need to be conducted before any conclusions can be drawn about the precipitation mechanisms.

We investigate the growth of the Nevanlinna Characteristic of f(z+\eta) for a fixed \eta in this paper. In particular, we obtain a precise asymptotic relation between T(r,f(z+\eta) and T(r,f), which is only true for finite order meromorphic functions. We have also obtained the proximity function and pointwise estimates of f(z+\eta)/f(z) which is a version of discrete analogue of the logarithmic derivative of f(z). We apply these results to give growth estimates of meromorphic solutions to higher order linear difference equations. This also solves an old problem of Whittaker concerning a first order difference equation. We show by giving a number of examples that all these results are best possible in certain senses. Finally, we give a direct proof of a result by Ablowitz, Halburd and Herbst., Comment: Accepted by The Ramanujan Journal on the 26th October 2005; galley proof version updated on the 9th Novermber 2007; deleted footnote 2, page 2 and reference 33 in the final galley proof

We investigate the growth of the Nevanlinna Characteristic of f(z+��) for a fixed ��in this paper. In particular, we obtain a precise asymptotic relation between T(r,f(z+��) and T(r,f), which is only true for finite order meromorphic functions. We have also obtained the proximity function and pointwise estimates of f(z+��)/f(z) which is a version of discrete analogue of the logarithmic derivative of f(z). We apply these results to give growth estimates of meromorphic solutions to higher order linear difference equations. This also solves an old problem of Whittaker concerning a first order difference equation. We show by giving a number of examples that all these results are best possible in certain senses. Finally, we give a direct proof of a result by Ablowitz, Halburd and Herbst., Accepted by The Ramanujan Journal on the 26th October 2005; galley proof version updated on the 9th Novermber 2007; deleted footnote 2, page 2 and reference 33 in the final galley proof

Let $(\cal Z \, , \, C)$ be an ordered Hausdorff real topological vector space. Some conditions for assuring that a nonempty set $K \subset {\cal Z}$ has a nonempty superior or inferior are established. Ordering-conically compact ordered Hausdorff real topological vector spaces are introduced so that in such a space every nonempty bounded below (respectively, bounded above) set has a nonempty inferior (respectively, superior).

Bibliography: leaves 160-167.

Semiconductor technology has moved in an accelerating pace. memory devices drive density and the main efforts are in cell architecture and contact shrink. Logic devices, on the other hand, drive performance and the emphases are on poly gate CD and interconnect efficiency. In this paper, logic device trends will be presented and their impact on mask making technology will be discussed. Challenges in mask blanks, poly CD control, large data file size, applications of resolution enhancement techniques will be covered. Recent market environment and its implication for mask/reticle cost consideration will also be presented. Finally challenges on a different dimension and scale in post-optical lithography mask making will be discussed.

Bibliography: pages 126-130., We survey the p-median problem and the p-centre problem. Then we investigate two new techniques for continuous optimal partitioning of a tree T with n - 1 edges, where a nonnegative rational valued weight is associated with each edge. The continuous Max-Min tree partition problem (the continuous Min-Max tree partition problem) is to cut the edges in p - 1 places, so as to maximize (respectively minimize) the weight of the lightest (respectively heaviest) resulting subtree. Thus the tree is partitioned into approximately equal components. For each optimization problem, an inefficient implementation of the algorithm is given, which runs in pseudo-polynomial time, using a previously developed algorithm and a construction. We then derive from it a much faster algorithm using a top-down greedy technique, which runs in polynomial time. The algorithms have a variety of applications among others to highway and pipeline maintenance.

Despite growth in the use of ophthalmologic care in the last decade, little is known about the use of eye care services and patterns of physician contact across population subgroups. As the U.S. population grows older, such information is crucial in planning strategies for treatment and prevention of eye disorders as well as in identifying potential problems in access and use of eye care. Using the 1990 National Ambulatory Medical Care Survey data, a descriptive statistical analysis was employed to profile the possible variations in eye care-related office visits to ophthalmologists and other physicians across demographic groups. In 1990, a total of 49.3 million visits that were related primarily to an ocular disorder were made to physicians' offices; 43.8 million (89 percent) of these were visits to ophthalmologists and 5.4 million (11 percent) to other physicians. Use of ambulatory eye care varied across demographic subgroups. Those ages 65 or older had a substantially higher rate of eye care related outpatient visits per 1,000 persons per year compared with the rest of the population (743.6 per 1,000 versus 118.5 per 1,000, P0.001). Women had a higher rate than men (216.0 per 1,000 versus 177.0 per 1,000, 0.01; P0.05). Blacks had a substantially lower rate than whites (143.2 per 1,000 versus 194.6 per 1,000, 0.001; P0.01). Those who visited ophthalmologists' offices also differed from those who visited other physicians' offices in terms of their age, sex, race, health insurance status, and disease characteristics. It is important to devote increased attention to the prevention of vision loss among the population groups that have a higher risk of developing eye diseases and that also may have underused or have less access to care. Results from this analysis, in combination with data on the prevalence of ocular disorders for different population groups, provide useful information to identify these high-risk groups.

Proliferation potential and extracellular matrix production were compared in cultured porcine glomerular mesangial cells and arterial and venous smooth muscle cells. Mesangial and arterial smooth muscle cells proliferated more rapidly than venous smooth muscle cells. In immunofluorescence studies, mesangial and arterial smooth muscle cells stained strongly for collagen types I, III, and V; venous smooth muscles showed weaker staining for collagens III and V. Total collagen synthesis in cultured mesangial and arterial smooth muscle cells was lower than in venous smooth muscle cells. Electrophoretic analysis showed type I collagen predominated in all cell types, although levels were highest in mesangial and arterial smooth muscle cells. Collagen V (alpha 3) occurred only in venous smooth muscle cells. Mesangial and arterial smooth muscle cells showed cellbound fibronectin and laminin, which also were secreted into the medium. Venous smooth muscle cells secreted fibronectin, but all laminin was cell bound. The findings suggest a strong similarity between mesangial and arterial smooth muscle cells.

An attempt is made to combine the best features of two materials by forming a heterojunction consisting of a thin film of polycrystalline n-type TiO/sub 2/ deposited on n-type polycrystalline Fe/sub 2/O/sub 3/. Evidence is presented that, under illumination, holes generated in the Fe/sub 2/O/sub 3/ participate in the water decomposition reaction. That is, incident light (2.2

Etude du vieillissement d'anodes en TiO 2 relativement fortement dopees dans l'obscurite exposees a une solution a 0,1 N de NaOH pendant des durees superieures a 100 heures

There is evidence that the neuroendocrine system can be modulated by endogenous opioid peptides (for a review see ref. 1). Recently Rotsztejn et al.2 have ruled out a direct effect of Met-enkephalin on release of gonadotropin-releasing hormone (GnRH). Instead they postulated that Met-enkephalin inhibits the secretion of dopamine from dopaminergic neurones thereby reducing the dopamine-stimulated release of GnRH from the hypothalamus. We report here evidence that GnRH can itself supress dopamine synthesis in the rat. The fact that the dopamine neurone and GnRH-secreting cell are adjacent to each other3 suggests a feedback mechanism of regulating GnRH release.

In 1990, a clinical trial was started using retroviral-mediated transfer of the adenosine deaminase (ADA) gene into the T cells of two children with severe combined immunodeficiency (ADA− SCID). The number of blood T cells normalized as did many cellular and humoral immune responses. Gene treatment ended after 2 years, but integrated vector and ADA gene expression in T cells persisted. Although many components remain to be perfected, it is concluded here that gene therapy can be a safe and effective addition to treatment for some patients with this severe immunodeficiency disease.