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When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon–nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure1–3, and mapping out the strength and the isospin structure (neutron–proton (np) versus proton–proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3–5. Two-nucleon knockout or ‘triple coincidence’ reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6–8have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon–nucleon interaction.

The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton’s bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities1that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities2map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades2. Here we report measurements of the proton’s electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton’s electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.

AbstractMobile Wireless Mesh Network (MWMN) consists of numerous wireless sensors, the energy and communication ability of which are limited, and they send the sensing data to the receivers through mutual cooperation. In the next generation of network, wireless mesh networks are expected to play a more important role in mobile applications. Multicast communication is an effective way to save energy, bandwidth, cost and other resources in MWMN, so we propose a new Extended Ad hoc On-Demand Distance Vector (EAODV) routing method of MWMN in this paper. The new EAODV routing method chooses the forwarding routes, which can connect more multicast receivers to solve routing optimization problems. The method proposes a dynamic strategy to change the multicast tree structure based on the characteristic of node mobility of wireless network. It tries to minimize the energy consumption to extend the lifetime of the network, while an energy-balanced routing method can help to make the network lifetime longer by using the energy in a balanced way. Simulation results demonstrate that our method effectively improves the efficiency of multicast routing, the advantage and novelty of the approach suggested is its good performance in many aspects of mobile applications.

Going from a diatomic to a polyatomic linear or non-linear molecule, the description of molecular frame photoemission in photoionization of molecules involves a function of increasing complexity. Using the electron-ion Vector Correlation method, which provides the emission velocity vectors of the emitted charged particles in a dissociative photoionization reaction, generally gives access to Recoil Frame Photoelectron Angular Distributions (RFPADs). We report results for site selected inner-shell photoionization of the N2O molecule induced by elliptically polarized light, where the primary ionization reaction leads to the production of several fragmentation channels. Ion fragment kinetic energy release distributions as well as RFPADs are reported for selected two ion-channels containing the complete parent molecule. Experimental results are compared with recent multi-channel Schwinger configuration interaction (MCSCI) ab initiocalculations at the level of the RFPADs. The link with the original computed molecular frame photoelectron angular distributions (MFPADs) is discussed.

Increasing evidence suggests that the activity of cysteine proteases, including cathepsin L, is important in cancer cell invasion and metastasis. This study was designed to investigate the clinicopathological and prognostic significance of cathepsin L in human urothelial carcinoma of the bladder (UCB). Standard immunohistochemistry was used to determine the presence of cathepsin L and Ki-67 (a marker of proliferation) in paraffin-embedded specimens of 82 human UCB cases. Cathepsin L protein was localized in the cytoplasm of the malignant UCB cells, and was significantly associated with the pathological tumour stage (invasiveness), tumour grade, survival, local tumour recurrence during follow-up, the occurrence of distant metastasis during follow-up and the presence of Ki-67 protein. Multivariate analysis using the Cox proportional hazards model revealed that cathepsin L immunopositivity and pathological tumour stage (invasiveness) were independent significant prognostic factors for overall survival. This study showed that cathepsin L provides significant prognostic information and that it might be a useful therapeutic target in the future.

The mysterious death of the former secret service agent Alexander Litvinenko on 23 November 2006 suddenly attracted the attention of the public to the rather unknown radionuclide 210Po. In this respect, this paper presents some general background information about this radionuclide as well as some details about its biokinetic behaviour and internal dosimetry. The results are discussed in the context of the Litvinenko case with regard to possible health effects on people from Germany being potentially contaminated. However, no evidence for contamination with 210Po could be found for any people tested at the GSF-National Research Center for Environment and Health (since 01.01.2008 Helmholtz Zentrum München).

Abstract: Going from a diatomic to a polyatomic linear or non-linear molecule, the description of molecular frame photoemission in photoionization of molecules involves a function of increasing complexity. Using the electron-ion Vector Correlation method, which provides the emission velocity vectors of the emitted charged particles in a dissociative photoionization reaction, generally gives access to Recoil Frame Photoelectron Angular Distributions (RFPADs). We report results for site selected inner-shell photoionization of the N2O molecule induced by elliptically polarized light, where the primary ionization reaction leads to the production of several fragmentation channels. Ion fragment kinetic energy release distributions as well as RFPADs are reported for selected two ion-channels containing the complete parent molecule. Experimental results are compared with recent multi-channel Schwinger configuration interaction (MCSCI) ab initio calculations at the level of the RFPADs. The link with the original computed molecular frame photoelectron angular distributions (MFPADs) is discussed.

The Maoniuping rare-earth-element (REE) deposit, hosted in a carbonatite-syenite complex, is the second largest light REE deposit in China. Fluorite is one of the main gangue minerals. Fluorites with different colors and REE patterns show uniform initial 87Sr/86Sr ratios and εNd values, similar to carbonatite and syenite, and different from granite. Chondrite-normalized REE patterns of early fluorite and quartz resemble those of carbonatite and syenite, but differ from those of granite and rhyolite. These indicate that the REE ore-forming fluids are closely related to carbonatite and syenite magmas. Because emplacement of the carbonatite was later than that of the syenite, early fluid carrying REE and fluoride mainly evolved from the syenite magma. Mixing of this fluid with a Ca-, carbonatite-derived fluid was the major control of early fluorite deposition. With changes in temperature of the ore-forming fluids, REE mineral deposition occurred as a result of the decreased ligand concentration that accompanied massive later fluorite mineralization. The uniform isotope compositions of fluorite, quartz, and carbonatite show that the REE ore-forming fluids were not contaminated by ground or meteoric water or by country-rock fluids.

Abstract: Expansion mutations of trinucleotide repeats and other units of unstable DNA have been proposed to account for at least some of the genetic susceptibility to a number of neuropsychiatric disorders, including bipolar affective disorder, schizophrenia, autism, and panic disorder. To generate additional candidate genes for these and other disorders, cDNA libraries from human brain were probed at high stringency for clones containing CCG, CGC, GCC, CGG, GCG, and GGC repeats (referred to collectively as CCG repeats). Some 18 cDNAs containing previously unpublished or uncharacterized repeats were characterized for chromosomal locus, repeat length polymorphism, and similarity to genes of known function. The cDNAs were also compared with the 37 human genes with eight or more consecutive CCG triplets in GenBank. The repeats were mapped to a number of loci, including 1p34, 2p11.2, 2q30–32, 3p21, 3p22, 4q35, 6q22, 7qter, 13p13, 17q24, 18p11, 19p13.3, 20q12, 20q13.3, and 22q12. Length polymorphism was detected in 50% of the repeats. The newly cloned cDNAs include a complete transcript of human neurexin-1B, a portion of BCNG-1 (a newly described brain-specific ion channel), a previously unreported polymorphic repeat located in the 5’ UTR region of the guanine nucleotide-binding protein (G-protein) β2 subunit, and a human version of the mouse proline-rich protein 7. This list of cDNAs should expedite the search for expansion mutations associated with diseases of the central nervous system.

Excitatory inputs to neurons in the Forel's field H (FFH) related to visually induced vertical saccades from the ipsilateral superior colliculus (SC) were investigated in chronically prepared alert cats. By stimulation of the deep or intermediate layer of the SC, upward augmenting neurons (ANs) and one long-lead downward burst neuron (BN) were found to be activated monosynaptically, while medium-lead BNs were activated disynaptically. The monosynaptically activated neurons were not antidromically activated from the oculomotor nucleus, whereas disynaptically activated neurons were also activated antidromically from the inferior rectus subdivision of the nucleus. These results suggest that an excitatory input to the FFH from the SC for inducing vertical saccades of visual origin first reaches upward ANs and/or long-lead downward BNs in the FFH, which in turn drive medium-lead BNs in the same area synapsing with motoneurons related to vertical eye movements.

We have developed an experimental arrangement for measuring Rayleigh scattering in liquids and liquid mixtures that are either in thermal equilibrium or in thermal nonequilibrium states. As an illustrative example we report experimental values for the thermal dilfusivity, the mass diffusion coefficient, the Rayleigh-factor ratio, and the Suret coefficient of an equimolar mixture of liquid toluene andn-hexane.

The nucleotide sequence of the fabA gene encoding beta-hydroxydecanoyl thioester dehydrase, a key enzyme of the unsaturated fatty acid synthesis pathway of Escherichia coli, has been determined by the dideoxynucleotide sequencing technique. Most of the sequence was obtained by sequencing intragenic insertions of the transposon, Tn1000, isolated in vivo. A synthetic primer complementary to a portion of the inverted repeat sequences at the ends of the transposon was used to prime DNA synthesis into the flanking fabA sequences. The gene is composed of 516 nucleotides (171 amino acid residues) encoding a protein with a molecular weight of 18,800. Approximately half of the derived amino acid sequence was confirmed by automated Edman sequencing of peptides obtained by cyanogen bromide cleavage. The active site histidine residue (His-70) has been identified by analysis of the peptides labeled by reaction with 14C-labeled 3-decynoyl-N-acetylcysteamine, a specific mechanism-activated inhibitor. A cysteine residue (Cys-69) adjacent to the active site histidine may play the role in catalysis previously assigned to a tyrosine residue. We also report a simplified purification process for the dehydrase beginning with extracts of a brain which greatly overproduces the enzyme.

We describe the vaccination of Panamanian monkeys (Aotus sp.) with two recombinant blood stage antigens that each contain a portion of the N-terminal region of the SERA (serine repeat antigen) protein of the malaria parasite Plasmodium falciparum. We immunized with either a 262-amino-acid SERA fragment (SERA I) that contains amino acids 24 to 285 of the 989-amino-acid protein or a 483-amino-acid SERA fragment (SERA N) that contains amino acids 24 to 506 as part of a fusion protein with human gamma interferon. The recombinant proteins were shown to stimulate protective immunity when administered with complete and incomplete Freund adjuvant. Four of six immunized monkeys challenged by intravenous inoculation with blood stage P. falciparum developed parasitemias that were reduced by at least 1,000-fold. Two of six immunized monkeys developed parasitemias which were comparable to the lowest parasitemia in one of four controls and were 50- to 1,000-fold lower than in the other three controls.

Retroviral vectors were used to introduce the wild-type p53 gene into human bladder cancer cell lines BIU-87 and EJ, which express endogenous wt-p53 gene and have a mutation in H-ras gene. The expression of the exogenous wt-p53 gene in cells suppresses the growth of the bladder cancer cells in standard culture and in soft agar and blocks the cell cycle progression in G1. The BIU-87 and EJ cells developed tumors with average volumes of 6.53 cm3 and 6.61 cm3 in nude mice in 9 weeks after inoculation, while the cells transduced with wt-p53 gene failed to form tumors. The expression of H-ras gene in bladder cancer cells was reduced at mRNA level. These results suggest that the overexpression of the wt-p53 gene suppresses the expression of mutant H-ras gene and inhibits the tumor cell growth in vivo and in vitro.

A simple analytical solution is developed for calculating the residual stresses which occur as a result of the laser transformation hardening of steel surfaces. The solution is based mainly on taking account of the dilatation resulting from the martensitic transformation and allows the influence of the many and varied parameters involved in laser transformation hardening (beam size and intensity, material properties, composition, etc.) to be readily assessed. Satisfactory agreement between the theoretical predictions and reported experilnental measurements of residual stress is obtained.

Alkaline phosphatase (ALP) in human choriocarcinoma cells (malignant trophoblasts) was characterized by its greater sensitivity to EDTA and l-leucine inhibition as compared with the placental isozyme. In addition, both the fully processed and the nonglycosylated forms of choriocarcinoma ALP migrated faster than the corresponding placental enzyme in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Choriocarcinoma cells express a 2.6-kilobase (kb) ALP mRNA unlike normal human placenta which expresses a 2.8-kb ALP mRNA. Administration of sodium butyrate to choriocarcinoma cells greatly increased the steady-state levels of the 2.6-kb choriocarcinoma ALP mRNA, which resulted in an increase in enzyme activity and biosynthesis. S1 nuclease analysis using probes derived from a placental ALP cDNA and ribonuclease protection assays employing probes derived from the germ cell ALP gene demonstrated that choriocarcinoma cells express the germ cell ALP gene. The germ cell ALP gene encodes the placental ALP-like isozyme that is primarily expressed in the thymus, testis, and germ cell tumors. The structures of the internal exons (II–X) of the germ cell ALP gene were determined previously based on their similarity to the placental ALP gene. However, the boundaries of exons I and XI (3′ exon) of the germ cell ALP gene were not defined due to sequence divergence between the two genes at the 5′ and 3′ regions. Ribonuclease protection and primer extension assays demonstrated that exon I of this gene is 119 base pairs in length and that germ cell ALP mRNA contains one major transcription initiation site. The isolation and characterization of germ cell ALP cDNA clones from a butyrate-treated choriocarcinoma cDNA library showed that the germ cell ALP mRNA is 2487 bases in length and exon XI of this gene is 1135 base pairs long.

Hot isostatic pressing (hipping) is an extremely efficient way of densifying ceramic and high alloy metallic powders, or for healing porosity in castings. However, depending on the parameters of pressure, temperature, rate of heating, and sample size, hipping can result in a non-uniform mode of densification. This mainly occurs when a rapidly heated sample, or a sample of large dimensions, densifies quickly at the surface to produce, in effect, a fully dense, hard shell. It is shown in this paper that there can be a number of negative factors resulting from this, including reduced rates of densification, sample shape change, non-uniform shrinkage, and the development of residual stresses in the sample. Criteria for predicting whether or not non-uniform densification will occur are presented and evaluated. PM/0554

An analytical model of the heat flow during pulsed welding is constructed by first developing a solution for the temperature distribution due to an instantaneous, stationary, Gaussian heat source. This solution is first extended to treat the case of a moving heat source for a single pulse and then extended to treat the case of pulsed welding by summing the temperature changes due to a series of pulses. Test gas tungsten arc welds in mild steel are used to confirm the validity of the model.MST/1371

Genomic DNA clones that coded for the bifunctional dihydrofolate reductase (DHFR) and thymidylate synthase (TS) (DHFR-TS) activities from a pyrimethamine-sensitive strain of Plasmodium falciparum were isolated and sequenced. The deduced DHFR-TS protein contained 608 amino acids (71,682 Da). The coding region for DHFR-TS contained no intervening sequences and had a high A + T content (75%). The DHFR domain, in the amino-terminal portion of the protein, was joined by a 94-amino acid junction sequence to the TS domain in the carboxyl-terminal portion of the protein. The TS domain was more conserved than the DHFR domain and both P. falciparum domains were more homologous to eukaryotic than to prokaryotic forms of the enzymes. Predicted secondary structures of the DHFR and TS domains were nearly identical to the structures identified in other DHFR and TS enzymes.

The present state of hipping modelling is briefly reviewed using the principles of densification theory and plastic deformation theory for porous materials on the basis of a macro- and microscopic approach. The features of these two approaches are discussed. The constitutive equation for a porous compact relating the strains and stresses (macroscopic approach) is modified by incorporating the rate equations for densification mechanisms (microscopic approach). A new modified constitutive equation is then derived which combines the advantages of both approaches. Based on this equation, the hipping process can be simulated. The density and shape change of a porous compact during densification or deformation processes under conditions of either isostatic or nonisostatic pressure can be predicted. PM/0645

In order to achieve penetration damage efficiently under larger standoff distance condition, a shaped charge warhead is designed on the basis of jetting penetrator charges (JPC) formation and disruption theory. The paper analyses the formation, elongation and disruption processes of JPC by using LS-DYNA software. The results show that JPC tail begins to break away at 8.5 charge diameters (CD) standoff distance. When the standoff increases, JPC head velocity decrease while JPC tail increase, and JPC length-diameter ratio increased significantly. Based on numerical simulation and theoretical investigation, it was found that the JPC still has good penetration ability at 15.5CD standoff distance, and JPC effective standoff is able to reach 20CD distance. The result provides a reference for the design of JPC warhead at large standoff distance.

For coal-fired power plants, the application of blended coal combustion has been a great issue due to the shortage and rising prices of high-rank coal. This paper describes the optimization of blending methods between Xing'an lignite coal, Shaltala lignite coal, Ura lignite coal, and Inner Mongolia bituminous coal. The multi-objective decision-making method based on fuzzy mathematics was used to determine the optimal blending ratio to improve the power plant coal-fired economy.

In this paper, the supercritical boiler thermodynamic calculation model is studied. Three types of heat exchangers are proposed, namely furnace (total radiation type), semi-radiation and convection, and discussed. Two cases were simulated - mixing of two bituminous coals and mixing of a bituminous coal and lignite- order to analyze the performance on the flue gas side. The study shows that the influence of flue air leakage and gas distribution coefficient on the system.

The corrosion behavior of two cast Fe-xCr-5Si (x= 0, 5 at.%) alloys has been studied at 800°C in H2-CO2-H2S mixture. The addition of 5 at.% Cr improved the corrosion resistance of the Fe-5Si alloy by forming a protective scale of mixed Cr2O3and SiO2at the bottom of a non-uniform scale. The corrosion resistance of the cast Fe-5Cr-5Si alloy was further improved by a magnetron-sputtered film of identical composition that promoted the formation of a protective scale of a Cr2O3-SiO2mixture at the coating/alloy interface. The mechanisms of forming the protective scales are examined and analyzed.

Radiation doses of radiopharmaceuticals to patients in nuclear medicine are, as the standard method, estimated by the administered activity, medical imaging (e.g. PET imaging), compartmental modeling and Monte Carlo simulation of radiation with reference digital human phantoms. However, in each of the contributing terms, individual uncertainty due to measurement techniques, patient variability and computation methods may propagate to the uncertainties of the calculated organ doses to the individual patient. To evaluate the overall uncertainties and the quality assurance of internal absorbed doses, a method was developed within the framework of the MADEIRA Project (Minimizing Activity and Dose with Enhanced Image quality by Radiopharmaceutical Administrations) to quantitatively analyze the uncertainties in each component of the organ absorbed doses after administration of 18F-choline to prostate cancer patients undergoing nuclear medicine diagnostics. First, on the basis of the organ PET and CT images of the patients as well as blood and urine samples, a model structure of 18F-choline was developed and the uncertainties of the model parameters were determined. Second, the model parameter values were sampled and biokinetic modeling using these sampled parameter values were performed. Third, the uncertainties of the new specific absorbed fraction (SAF) values derived with different phantoms representing individual patients were presented. Finally, the uncertainties of absorbed doses to the patients were calculated by applying the ICRP/ICRU adult male reference computational phantom. In addition to the uncertainty analysis, the sensitivity of the model parameters on the organ PET images and absorbed doses was indicated by coupling the model input and output using regression and partial correlation analysis. The results showed that the uncertainty factors of absorbed dose to patients are in most cases less than a factor of 2 without taking into account the uncertainties caused by the variability and uncertainty of individual human phantoms. The sensitivity study showed that the metabolic transfer parameter from the blood to soft tissues has a strong influence on blood sample collection from the beginning until 500 min. post administration; the transfer pathways between blood and liver impact strongly the liver imaging during the time course. The results of this study suggest that organ image acquisition of liver and kidneys after 100 min. as well as blood and urine sample collection are necessary for the reduction of uncertainties of absorbed dose estimates to patients.