Analysis of Trends in Construction Research: 1985–2002

This paper provides a historical perspective on construction research trends as reflected in the American Society of Civil Engineer’s Journal of Construction Engineering and Management (JCEM). The paper reports the results of an 18-year analysis of JCEM between 1985 and 2002. The analysis focused on such data as author information (affiliations and home countries), as well as the research topics of the technical papers. The paper summarizes the data extracted from the journal and use it to analyze construction research trends. Construction trends reveal that U.S. writers contributed the most papers by that there has been an increasing number of international submissions to the journal. The top research topical areas relate to scheduling, productivity, constructability, simulation, cost control, planning, safety, and computer systems as described in this paper show that research is increasing throughout the world and topics are changing as current needs change. However, there is a need to increase research collaboration between industry and academia, government and academia, and industry and government to advance the construction industry.     

KCNK3 Mutation Causes Altered Immune Function in Pulmonary Arterial Hypertension Patients and Mouse Models

Loss of function KCNK3 mutation is one of the gene variants driving hereditary pulmonary arterial hypertension (PAH). KCNK3 is expressed in several cell and tissue types on both membrane and endoplasmic reticulum and potentially plays a role in multiple pathological process associated with PAH. However, the role of various stressors driving the susceptibility of KCNK3 mutation to PAH is unknown. Hence, we exposed kcnk3^fl/fl animals to hypoxia, metabolic diet and low dose lipopolysaccharide (LPS) and performed molecular characterization of their tissue. We also used tissue samples from KCNK3 patients (skin fibroblast derived inducible pluripotent stem cells, blood, lungs, peripheral blood mononuclear cells) and performed microarray, immunohistochemistry (IHC) and mass cytometry time of flight (CyTOF) experiments. Although a hypoxic insult did not alter vascular tone in kcnk3^fl/fl mice, RNASeq study of these lungs implied that inflammatory and metabolic factors were altered, and the follow-up diet study demonstrated a dysregulation of bone marrow cells in kcnk3^fl/fl mice. Finally, a low dose LPS study clearly showed that inflammation could be a possible second hit driving PAH in kcnk3^fl/fl mice. Multiplex, IHC and CyTOF immunophenotyping studies on human samples confirmed the mouse data and strongly indicated that cell mediated, and innate immune responses may drive PAH susceptibility in these patients. In conclusion, loss of function KCNK3 mutation alters various physiological processes from vascular tone to metabolic diet through inflammation. Our data suggests that altered circulating immune cells may drive PAH susceptibility in patients with KCNK3 mutation.     

Bounding the firing synchronization problem on a ring

In this paper we improve the upper and lower bounds on the complexity of solutions to the firing synchronization problem on a ring. In this variant of the firing synchronization problem the goal is to synchronize a ring of identical finite automata. Initially, all automata are in the same state except for one automaton that is designated as the initiator for the synchronization. The goal is to define the set of states and the transition function for the automata so that all machines enter a special fire state for the first time and simultaneously during the final round of the computation. In our work we present two solutions to the ring firing synchronization problem, an 8-state minimal-time solution and a 6-state non-minimal-time solution. Both solutions use fewer states than the previous best-known minimal-time automaton, a 16-state solution due to Culik. We also give the first lower bounds on the number of states needed for solutions to the ring firing synchronization problem. We show that there is no 3-state solution and no 4-state, symmetric, minimal-time solution for the ring.     

Employing subgroup evolution for irregular-shape nesting

This paper introduces a new method to solve the irregular-shape, full-rotation nesting problem by a genetic algorithm. Layout patterns are evolved in hierarchical subgroups to facilitate the search for an optimal solution in such a complex solution space. The genotype used in the genetic algorithm contains both the sequence and rotation for each shape, requiring new genetic operators to manipulate a multi-type genetic representation. A lower-left placement heuristic coupled with matrix encoding of the shapes and plate prevents overlap and constrains the solution space to valid solutions. This new method is able to efficiently search the solution space for large problems involving complex shapes with 360 degrees of freedom. The algorithm generates better solutions than previously published evolutionary methods.     

Automated Construction of an Open Reading Frame Library from Sinorhizobium meliloti

An automated, high-throughput, open reading frame (ORF) library construction process has been developed. ORFs from genomic DNA of the microbe Sinorhizobium meliloti were amplified by PCR and cloned into the library vector by homologous recombination instead of traditional ligation. From 960 targets, we successfully generated 723 (75.3%) ORFs from the initial PCR. After cloning the successful samples into the library vector, transforming into E. coli and PCR colony screening, 371 (38.6% overall) ORFs were placed into the new library and sequenced. Our prototype library contained 314 (32.7% overall) clones with sequence identity to the Sinorhizobium meliloti genome.     

Implementation and analysis of an on-farm food safety program for the production of greenhouse vegetables

Fresh fruits and vegetables are increasingly being recognized as vectors for foodborne illness. In 1998, an on-farm food safety program was developed for the Ontario Greenhouse Vegetable Growers (OGVG) in Ontario, Canada. This hazard analysis critical control point-based system was designed to reduce the potential of microbial contamination along the entire production and distribution process. A previous report (D. A. Powell, M. Bobadilla-Ruiz, A. Whitfield, M. W. Griffiths, and A. Luedtke, J. Food Prot. 65:918-923) outlined the first 2 years of the program; the present report documents the third year of the program's implementation. Through individual on-site grower visits and the microbiological testing of produce and water, the program's OGVG member requirements were determined, and the program's success was assessed. Growers' knowledge, understanding, and awareness of microbial risks associated with fresh produce have increased, and improvements in practices used in greenhouses and packing sheds were noted.     

Properties of lysophosphatidylcholine acyltransferase from <Emphasis Type="Italic">Brassica napus</Emphasis> cultures

Acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT; EC 2.3.1.23) catalyzes the acyl-CoA-dependent acylation of lysophosphatidylcholine (LPC) to produce PC and CoA. LPCAT activity may affect the incorporation of fatty acyl moieties at the sn-2 position of PC where PUFA are formed and may indirectly influence seed TAG composition. LPCAT activity in microsomes prepared from microspore-derived cell suspension cultures of oilseed rape (Brassica napus L. cv Jet Neuf) was assayed using [1-¹⁴C]acyl-CoA as the fatty acyl donor. LPCAT activity was optimal at neutral pH and 35°C, and was inhibited by 50% at a BSA concentration of 3 mg mL⁻¹. At acyl-CoA concentrations above 20 μM, LPCAT activity was more specific for oleoyl (18∶1)-CoA than stearoyl (18∶0)- and palmitoyl (16∶0)-CoA. Lauroyl (12∶0)-CoA, however, was not an effective acyl donor. LPC species containing 12∶0, 16∶0, 18∶0, or 18∶1 as the fatty acyl moiety all served as effective acyl acceptors for LPCAT, although 12∶0-LPC was somewhat less effective as a substrate at lower concentrations. The failure of LPCAT to catalyze the incorporation of a 12∶0 moiety from acyl-CoA into PC is consistent with the tendency of acyltransferases to discriminate against incorporation of this fatty acyl moiety at the sn-2 position of TAG from the seed oil of transgenic B. napus expressing a medium-chain thioesterase.     

Improved Efficiency in Blue Phosphorescent Organic Light‐Emitting Devices Using Host Materials of Lower Triplet Energy than the Phosphorescent Blue Emitter

Data from a series of phosphorescent blue organic light‐emitting devices with emissive layers consisting of either 4,4′‐bis(N‐carbazolyl)‐2,2′‐biphenyl (CBP):6% bis[(4,6‐difluorophenyl)pyridinato‐N,C²](picolinato)iridium(III) (FIrpic) or bis(9‐carbazolyl)benzene (mCP):6% FIrpic show that the triplet energy of the hole and electron transport layers can have a larger influence on the external quantum efficiency of an operating device than the triplet energy of the host material. A maximum external quantum efficiency of 14% was obtained for CBP:6% FIrpic devices which is nearly double all other published CBP:6% FIrpic results. A new host material, 4‐(diphenylphosphoryl)‐N,N‐di‐p‐tolylaniline (DHM‐A2), which has a triplet energy lower than that of FIrpic is also reported. Devices fabricated using DHM‐A2 show improved performance (lower drive voltage and higher external quantum efficiency) over devices using 4‐(diphenylphosphoryl)‐N,N‐diphenylaniline (HM‐A1), a high performance ambipolar DHM‐A2 analogue with a triplet energy greater than FIrpic. Nearly 18% external quantum efficiency was obtained for the DHM‐A2:5% FIrpic devices. The results suggest modified design rules for the development of high performance host materials: more focus can be placed on molecular structures that provide good charge transport (ambipolarity for charge balance) and good molecular stability (for long lifetimes) rather than first focusing on the triplet energy of the host material.     

Intravital imaging of human prostate cancer using viral nanoparticles targeted to gastrin-releasing Peptide receptors

Multivalent nanoparticles have several key advantages in terms of solubility, binding avidity, and uptake, making them particularly well suited to molecular imaging applications. Herein is reported the stepwise synthesis and characterization of NIR viral nanoparticles targeted to gastrin-releasing peptide receptors that are over-expressed in human prostate cancers. The pan-bombesin analogue, [β-Ala11, Phe13, Nle14]bombesin-(7-14), is conjugated to cowpea mosaic virus particles functionalized with an NIR dye (Alexa Fluor 647) and polyethylene glycol (PEG) using the copper(I)-catalyzed azide-alkyne cycloaddition reaction. Targeting and uptake in human PC-3 prostate cells is demonstrated in vitro. Tumor homing is observed using human prostate tumor xenografts on the chicken chorioallantoic membrane model using intravital imaging. Further development of this viral nanoparticle platform may open the door to potential clinical noninvasive molecular imaging strategies.     

淀粉直支比定量技术及其在食品领域中的应用

天然淀粉中含有直链和支链两种形式的α-D-葡聚糖,二者的相对含量不仅与淀粉的糊化、老化、凝胶等理化性质和食品功能有关,还决定着淀粉的经济价值。淀粉直支比定量技术在含淀粉的粮谷类作物育种、淀粉的高值化利用以及食品品质保障和创新等领域具有广泛的应用。本文综述了当前食品科学研究和加工制造领域对淀粉直支比定量技术的需求,介绍和对比了各种经典和新型淀粉直支比定量技术的原理、优缺点和适用性,对淀粉直支比定量技术在未来食品领域的潜在应用提出展望。