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Prediction models for enteric methane (CH4) emissions from beef cattle proposed by various groups may not perform with similar accuracy for the low- and middle-income countries in South-east Asia (SE-Asia) because beef cattle in these countries are raised under different climatic conditions with diverse feeding systems, and have different CH4 emission characteristics. The objectives of this study were to: i) predict CH4 emission (g d−1 animal−1), yield [g kg−1 dry matter intake; DMI)−1], intensity [g kg−1 average daily gain)−1], and CH4 conversion factor (Ym) using an intercountry database of individual animal records from SE-Asia; ii) evaluate the impact of different dietary forage contents (all-, high- and low-forage) representing the diverse feeding systems on CH4 emission, yield, intensity and Ym in SE-Asia; and iii) cross-validate equations from this study with published data. A total of 398 individual animal observations of beef cattle from SE-Asia were used for this analysis. Linear models developed by incrementally adding covariates revealed that CH4 emission model using only DMI fitted to all data had a root mean square prediction error (RMSPE) of 16.9%. Subsets containing data with 100% forage in the diet (all-forage), 50–85% (high-forage) and < 50% (low-forage) had an RMSPE of 16.5%, 14.7%, and 17.4%, respectively. Linear multiple equation based on DMI and dietary NDF concentration (DMI + NDF_C, RMSPE = 15.2%; all-data) improved prediction accuracy over that of DMI alone. The DMI + NDF_C models for all-forage (RMSPE = 14.6%) and high-forage subsets (RMSPE = 13.3%) except for low-forage (RMSPE = 16.4%), improved the precision and accuracy of CH4 emission prediction. Methane yield and CH4 emission intensity could not be reliably modelled with the current database. The present study provides improved CH4 prediction models for beef cattle managed under diverse feeding systems in SE-Asia and affirmed that region-specific models are needed to reliably predict beef cattle CH4 emission at national or regional levels, particularly for low- and middle-income countries.

The release of new global geopotential models (GGMs) has raised the question of whether these GGMs could now supplant the development of regional/local geoid models. For geodetic surveying purposes the importance of a geoid model fitted to the local condition will greatly help in the resolution of many vertical datum issues especially for an archipelagic country such as the Philippines. Since the geoid as a vertical reference surface is used to convert ellipsoidal heights acquired through GNSS survey to orthometric heights, it is vital that this should at least match the heights derived through geodetic levelling within the allowed accuracy. However, the issue of mean sea level (MSL) as vertical reference for geodetic levelling has introduced another issue of concern especially when it is exhibiting accelerated sea level rise (ASLR). The results of the validation and comparison of recent GGMs showed that EGM 2008 and the 2012 released EIGEN-6C2 both classified as combined type model have RMS around 14 and...

We propose a new design approach for high-throughput arithmetic circuits based on state transitions using single-flux-quantum (SFQ) logic circuits. Microprocessors have several complex interconnects in datapath including loops of data, to which only one SFQ pulse is allowed to be confined, and the loops can spoil the high-throughput nature of SFQ circuits. In our new approach, we regard an arithmetic circuit with loops as a sequential logic circuit, and we use nondestructive readout gates (NDROs) as storage elements of the internal state. We can eliminate the loops and achieve high throughput by translating calculations into transitions of the state stored in the NDROs. We have implemented a bit-serial adder with the proposed approach, and demonstrated 36-GHz operations using the niobium 2.5-kA/cm(2) standard process technology.

Objetivos: Caracterização de síndromes em indivíduos com FL/P associadas a MAC e anomalias cromossômicas e ampliação dos espectros fenotípicos de síndromes já descritas. Local de execução: Laboratório de Citogenética Humana e Serviço de Genética Clínica, HRAC-USP, Bauru-SP. Participantes: 15 indivíduos com fissura labiopalatina associada a múltiplas anomalias congênitas e alteração cromossômica estrutural em seu cariótipo. Intervenções/Variáveis: Avaliação genética-clínica, estudo citogenético/anomalias cromossômicas estruturais. Resultados: Dos 15 indivíduos, 8 eram do gênero masculino e 7, do gênero feminino, foram detectados: translocação equilibrada em 1 indivíduo, cromossomo derivado em 5, duplicação em 2, cromossomo recombinante com duplicação parcial de um cromossomo em 1, deleção em 2 e cromossomo em anel em 4. O indivíduo 14 apresentou associação de trissomia dos cromossomos sexuais e der(22)t(11;22) extranumerário. Conclusões: Caracterizou-se 7 quadros sindrômicos de etiologia cromossômica com fissura de lábio e/ou palato em seu quadro clínico (dup 3p, dup 4q, dup 7p, del 9p, del 18q, del 21q e dup 22q) e um quadro de padrão único com provável etiologia ambiental. Ampliou-se o espectro fenotípico das síndromes de duplicação 7p com a possível inclusão de esclerocórnea em seu quadro clínico, da deleção 9p com a adição de mais um caso de presença de hemangioma e da deleção 18q com a confirmação de dois casos adicionais de fístulas no lábio inferior. Objective: Characterization of syndromes presented by patients with cleft lip and palate (CL/P) associated with associated with multiple congenital anomalies (MMC) and chromosomal abnormalities and expansion of the phenotyipc spectrum of syndromes already described. Setting: Human Cytogenetics Laboratory and Clinical Genetics Service, HRAC-USP, Bauru-SP. Participants: 15 patients with cleft lip and palate associated with multiple congenital malformation and structural chromosome abnormalities in their karyotypes. Interventions/Variables: Clinical-genetic evaluation, cytogenetic analysis/structural chromosome abnormalities. Results: Among the 15 patients, 8 were of the masculine gender and 7, of feminine gender. In this sample, was detected reciprocal translocation in 1 patient, derivative chromosome in 5, duplication in 2, recombinant chromosome with partial duplication of one chromosome in 1, deletion in 2 and ring chromosome in 4. The individual 14 presented association of trisomy of sexual chromosomes and der (22)t(11;22) extranumerary. Conclusions: Were characterized 7 chromosomal syndromes with cleft lip and/or palate on their clinical pictures (dup 3p, dup 4q, dup 7p, del 9p, del 18q, del 21q and dup 22q) and a single case with probable ambiental cause; and were extended the phenotypic spectum of syndromes of duplication 7p with the possible inclusion of sclerocornea on its clinical picture, deletion 9p with the addition of one more case of presence of hemangioma and deletion 18q with the confirmation of two additional cases of lip pits in the lower lip.

We present single-crystal neutron scattering measurements of the spin-1/2 equilateral triangular-lattice antiferromagnet Ba_{3}CoSb_{2}O_{9}. Besides confirming that the Co^{2+} magnetic moments lie in the ab plane for zero magnetic field and then determining all the exchange parameters of the minimal quasi-2D spin Hamiltonian, we provide conclusive experimental evidence of magnon decay through observation of intrinsic line broadening. Through detailed comparisons with the linear and nonlinear spin-wave theories, we also point out that the large-S approximation, which is conventionally employed to predict magnon decay in noncollinear magnets, is inadequate to explain our experimental observation. Thus, our results call for a new theoretical framework for describing excitation spectra in low-dimensional frustrated magnets under strong quantum effects.

It is well known that one drawback for stress-ribbon bridges can be that significant horizontal reactions at the abutment can be generated and that they have low flexural stiffness. The latter prevents them from being used as roadway bridges. A new hybrid structure of stress-ribbon deck and truss has been proposed and was adopted in the construction of Nozomi Bridge in Japan, a roadway bridge opened to traffic in 2003. Static and dynamic behaviours of the hybrid structure have been studied analytically and experimentally. The results show that the hybrid bridge has advantages over the stress-ribbon deck bridge as it generates much less horizontal force in suspension cables and has higher flexural stiffness, suitable for use as a roadway bridge, and that the hybrid bridge has advantages over the truss bridge since it can be constructed without extensive falsework and without large erection equipment. In this paper, at first, the hybrid structure is described, then analytical and test results are used to sh...

We propose an integer multiplier with systolic array structure for single-flux-quantum (SFQ) technology. Since SFQ logic circuits work by pulse logic, suitable circuit structure for SFQ logic circuits is different from one for semiconductor logic circuits. The systolic array is a circuit structure for VLSIs and consists of regularly arranged simple processing elements. All signals of the proposed systolic multiplier flow from input to output unidirectionally. This feature matches concurrent-flow clocking well. For evaluating the proposed systolic multiplier, we have designed a 4-bit systolic multiplier, as well as a 4-bit array multiplier which is one of the most typical parallel multipliers, and have compared them with each other. From the results of the design and the digital simulation, the number of Josephson junctions (JJs) of the 4-bit systolic multiplier is almost the half of that of the 4-bit array multiplier, and the latency of the former is about 1.5 times longer than that of the latter. Our estimation of the performance of larger-scale multipliers shows that the proposed systolic multiplier achieves comparable latency to the array multiplier, using extremely smaller number of JJs when the bit-width of input becomes large. We have fabricated a 1-bit cell of the systolic multiplier using NEC standard Nb process and have successfully tested it at low speed. The proposed systolic integer multiplier is attractive for SFQ technology.

Proper nutritional management during the dry period is required to prevent metabolic disorders during the time of parturition and for potential increase milk yield during early lactation, especially under the heat of summer. The effect of prepartum diets on partitioning of nitrogen (N), calcium (Ca), phosphorus (P), magnesium (Mg) and potassium (K) during dry period and early lactation in summer was investigated. Nine cows were assigned to two groups and fed either control (group C: four cows) or high concentrate (group H: five cows) diets to meet 110% of their requirements before parturition. The proportion of concentrate in control diet was 35%, and that in the high concentrate diet was 45%. After parturition, all cows were fed the same diets ad libitum during lactation. Balance trials were conducted at 9, 8 and 7 days before parturition and at 12, 13 and 14 days after parturition. Before parturition, dry matter intake (DMI), DM and NFE digestibility in group C tended to be lower than those in group H. The retention of N (p

Heat stress causes oxidative stress, which decreases plasma levels of vitamin C, an antioxidative vitamin in pigs and poultry. We investigated the plasma vitamin C concentration in lactating cows exposed to a hot environment temperature. In the first experiment, plasma vitamin C concentrations of 8 lactating cows were measured in summer and autumn. The concentration was found to be significantly lower in summer. The second experiment was performed using 4 lactating cows in a crossover design. The ambient temperature was set at 18 °C in the control treatment and at 28 °C in the heat-stressing treatment. Milk yields and feed intake tended to be lower in the stressing than control treatment. Rectal temperature and respiration rate were significantly ( P P

We have designed a pipelined 8-bit-serial single-flux-quantum microprocessor with multiple ALUs, called CORE1 β. In the CORE1 β, two ALUs connected in cascade enable us to perform two calculations on serial data using a register-to-register instruction, to enhance the peak performance. In addition, we have introduced pipelining to boost the performance. Although the pipelining is a difficult technique that requires a complex design in the datapath, we have implemented a simplified pipeline with seven stages by using two techniques. One is the separation of clock signals for pipelining and bit processing, and the other is the introduction of new buffers driven by independent clock signals for reading and writing flexibly in order to ease the difficulty in timing design between the register file and the ALUs. According to the logic simulation, the peak performance of the designed microprocessor is estimated to be 1500 million operations per second with a power consumption of 3.3 mW. We have fabricated the CORE1 β chip by using the NEC 2.5 kA cm−2 niobium standard process, and confirmed the correct operations of several instructions using high-speed clocks.

A novel method of design for controllers of pipelined microprocessors using single-flux-quantum (SFQ) logic has been proposed. The proposed design approach is based on one hot encoding and is very suitable for designing a finite state machine using SFQ logic circuits, where each internal state of the microprocessor is represented by a flip-flop. In this approach, decoding of the internal state can be performed instantaneously, in contrast to the case in the conventional method using a binary state register. Moreover, pipelining is effectively implemented without increasing the circuit size because no pipeline registers are required in the one hot encoding. By using this method, we have designed a controller for our new SFQ microprocessors, which employs pipelining. The number of Josephson junctions of the newly designed controller is 1067, while the previous version without pipelining contains 1721 Josephson junctions. These results indicate that the proposed design approach is very effective for pipelined SFQ microprocessors. We have implemented a new controller using the NEC 2.5 kA cm−2 Nb standard process and confirmed its correct operation experimentally.

PurposeTo introduce an efficient two‐dimensional numerical procedure for a three‐dimensional internal flow through a complex passage with a small depth, in which the viscous effects from upper and lower walls are significant.Design/methodology/approachA set of two‐dimensional governing equations has been derived by integrating the full three‐dimensional Navier‐Stokes equations over the depth. Then, this set of the governing equations has been discretized using a finite volume method. Simple algorithm and quick scheme are used to solve the resulting discretized equations.FindingsA numerical experiment conducted to investigate the oscillation mechanism of a feedback fluidic oscillator reveals that the feedback passage plays an important role of transmitting the pressure rise to the control port, which triggers the jet stream to deflect towards the opposite side wall in the reaction region. Comparison of the prediction and experiment substantiates the validity of the present numerical procedure.Originality/valueThe two‐dimensional numerical procedure, proposed in this study, will be used by researchers and practitioners to investigate various kinds of complex passages with a small depth. Especially, those who are interested in fluidic devices may find it extremely convenient to conduct numerical experiments.

We have demonstrated the components of datapath toward single-flux-quantum microprocessors based on our new architecture called the forwarding architecture. In the forwarding architecture, we improve the performance by utilizing multiple ALUs to conceal the inefficiency of bit-serial processing. The key components of the datapath are a register file and cascaded ALUs. We have designed the register file to hold four bit-serial data with two read ports and one write port. In each ALU, we have implemented six functionalities: addition, subtraction, logical AND, OR and Exclusive OR operations, and comparison with zero. We have tested the register file and the ALU using high-speed on-chip testing, and confirmed the correct operations up to 18 GHz and 23 GHz, respectively.

We have successfully demonstrated an 8-bit microprocessor using passive transmission lines based on single-flux-quantum LSI technology. In the microprocessor designed here, called CORE1/spl alpha/6, a simple bit-serial architecture with seven instructions was employed. In the CORE1/spl alpha/6, the floor plan was designed with consideration toward integration of a memory, and superconductive passive transmission lines (PTLs) were used to connect circuit blocks. Utilization of PTLs helped us reduce the propagation delay in long interconnections. The design flexibility of the floor plan was enhanced and the performance of the microprocessor was improved by 20% compared with our previous design. The CORE1/spl alpha/6 was composed of 6319 Josephson junctions and 15 PTLs with power consumption of 2.1 mW. We have confirmed the complete operations of the CORE1/spl alpha/6 by on-chip high-speed tests. The maximum clock frequencies for bit operation and instruction execution have been found to be 18 GHz and 1.2 GHz, respectively, where the performance corresponds to 240 million instructions per second (MIPS).

Argon, krypton and xenon were puffed with and without simultaneous hydrogen gas puffing into Ohmically heated plasmas of the JT-60U tokamak with low plasma currents in order to study the capability of disruption mitigation. It was found that krypton gas puffing can provide a plasma termination with smaller amounts of runaway electrons in comparison to argon and xenon gas puffing.

We developed an initial-beam-loading compensation system for electron linacs. This system consists of a Δ Φ –A (phase-to-amplitude) modulator and a fast-phase detector. The Δ Φ –A modulator can modulate the phase and the amplitude of a low-power RF simultaneously. Low-power and high-power tests were successfully carried out at KEK. The result of the high-power tests show that our system can reduce the energy spread from 27 to 0.3% for a 300-mA average current. The system that we developed can be a powerful tool for initial-beam-loading compensation. In addition, a numerical calculation method using the power-flow matrix was formulated to perform a fast beam-energy calculation with a simple algorithm. This method can be used to obtain the target RF waveform for energy-spread compensation.

Objective Transforming growth factor-α (TGFA) was the first gene suggested to be associated with nonsyndromic cleft lip, cleft palate, or both (CL/ P). There are, however, still controversies of the effect of TGFA on the predisposition of this malformation. To contribute to a better understanding of the role of this gene in the occurrence of CL/P we undertook a case-control study including patients and controls ascertained in different regions of the country. Design We examined the C2/TaqI variant of the TGFA gene in 536 patients with nonsyndromic CL/P and 412 controls. The TGFA genotype frequencies in patients were compared with controls using chi-square or Fisher exact test. DNA, obtained from peripheral blood or buccal swabs, was genotyped for the TaqI polymorphism of TGFA. Setting The probands and corresponding controls were ascertained in different centers of Brazil, partly representing the ethnic admixture of our population. Results The TGFA genotype distribution was very similar in patients with CL/P ascertained in the three different regions of Brazil. However, a discrete difference was observed between controls of Säo Paulo and Ceará (chi-square = 3.605; p = 0.058), with a lower value of the C2/Taq allele frequency in controls of CE (0.04). These data reinforce that this polymorphic system is heterogenous among different ethnic groups. In addition, no evidence was found for an association of TGFA with CL/P in this case-control study. Conclusion These data further suggest that TGFA is not a relevant modifier locus for the occurrence of CL/P.

We present a non-destructive and real-time beam profile monitor using Fresnel zone plates (FZPs) and the measurement of an electron-beam size with this monitor in the KEK–Accelerator Test Facility (ATF) damping ring. The monitor system has the structure of a long-distance X-ray microscope, where two FZPs constitute an X-ray imaging optics. The synchrotron radiation from the electron beam at the bending magnet is monochromatized by a crystal monochromator and the transverse electron beam image is twenty times magnified by the two FZPs and detected on an X-ray CCD camera. The expected spatial resolution for the selected photon energy of 3.235 keV is sufficiently high to measure the horizontal and vertical beam sizes of the ATF damping ring. With the beam profile monitor, we succeeded in obtaining a clear electron-beam image and measuring the extremely small beam size less than 10 μm. The measured magnification of the X-ray imaging optics in the monitor system was in good agreement with the design value.

Partial-band interferences are known to have a deleterious effect on the receiver performance in frequency-hopping communication systems. We consider the rejection of such interferences using an array of sensors. A simple yet effective method is proposed based on a constant power algorithm. The principle behind this method is that partial-band interferences contribute to power variations in the received signal, hence, the idea to constrain the output power of the array to be constant in order to reject interferences. It is shown that the algorithm converges in a reasonably low number of hops. Additionally, it achieves a nearly optimal signal-to-interference-plus-noise ratio without requiring any information about the location of the desired user. Finally, its robustness to synchronization errors is illustrated via numerical simulations.

We consider the problem of estimating the direction of arrival (DOA) of a source in the presence of an intermittent jammer, i.e., a jammer that corrupts the signal of interest from time to time. This situation is encountered in slow frequency-hopped spread spectrum systems with partial time or partial band jamming. It has deleterious effects on the receiver performance, at least when a single antenna is used. We consider using an array of sensors to mitigate the effects of such an interference. The influence of the latter on the signal and jammer DOA estimates is studied. A general setup is introduced, and two different models are derived, depending on whether the jammer's presence indicators are considered deterministic or random. In both cases, the Cramer-Rao bounds (CRBs) are derived, and a numerical study of the CRB provides insights into the influence of the jammer's parameters. Additionally, it is shown that conventional methods such as ESPRIT can provide fairly accurate DOA estimates for this type of interference.

Many parameters of polymers exhibit breaks when temperature passes through glass transition. It is also often assumed that fractional free volume (FFV) at the glass transition temperature (Tg) has a standard value (the isofree volume concept). As gas diffusion (D) and permeability (P) coefficients depend on FFV, and mechanism of sorption and permeation is different above and below Tg, a question can be asked if D and P parameters of various gases in polymers have standard values at corresponding Tg, and, if not, how the values of D(Tg) and P(Tg) vary with Tg in different polymers. To examine this problem, two approaches were used: (1) extrapolation to Tg of numerous P and D values measured at ambient temperatures; (2) an analysis of direct data obtained in different polymers at their Tg. In both cases, qualitatively similar results were obtained: the D(Tg) and P(Tg) values increase with growing Tg independently of the nature of gas. Permselectivity Pi(Tg)/Pj(Tg) and selectivity of diffusion Di(Tg)/Dj(Tg) are reduced when Tg increases. The dependence of the solubility coefficients S(Tg) = D(Tg)/P(Tg) is much weaker than those of D(Tg) and P(Tg). This conclusion was confirmed by the results of direct measurements of S in a wide range of temperature including Tg for several gas/polymer systems. An analysis of the results of positron annihilation studies of free volume in polymers led to the conclusion that the observed increases in the D(Tg) and P(Tg) values with Tg are caused mainly by thermal activation of diffusion processes at Tg. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1691–1705, 2000

The gene coding for copalyl diphosphate synthase (CPS), which represents the first gene of the gibberellin pathway, was isolated from the rice pathogen Gibberella fujikuroi. This fungus is used commercially for the production of gibberellic acid and related gibberellins. CPS is a terpene cyclase which catalyzes the first specific step of the gibberellin (GA) pathway as it branches off from the general isoprenoid (biosynthetic) pathway at geranylgeranyl disphosphate (GGDP). A cDNA fragment of the cps gene from the fungus G. fujikuroi was amplified by RT-PCR using oligonucleotides based on amino-acid sequences which were conserved between the plant CPSs and the bifunctional CPS/KS of the fungus Phaeosphaeria sp. L487. A 588-bp fragment obtained with nested PCR was used to isolate the corresponding genomic clone of the cps gene from the wild-type lambda-library. This gene consists of three exons and two introns. The three exons are 2877 bp long and encode 959 amino-acid residues. The protein shares 48% identity with the bifunctional Phaeosphaeria sp. L487 FCPS and between 16% and 18% identity to the corresponding plant CPSs. Expression of the G. fujikuroi cps gene is strongly enhanced under conditions optimized for gibberellin biosynthesis and is reduced when high amounts of ammonium are present in the medium. Gene disruption, followed by gibberellin assays and Southern-blot analysis of the transformants, demonstrated clearly that the cloned gene has the expected function in the biosynthesis of fungal gibberellins.

A third-generation VUV and soft X-ray light source, the VSX light source in short, is being designed at the Institute for Solid State Physics of the University of Tokyo. It may produce a brilliance of more than 1020 photons s−1 mm−2 mrad−2 (0.1%b.w.)−1 at 1 keV photon energy with undulators installed in 14 m-long straight sections. The accelerator scheme for the VSX project consists of a linac, booster synchrotron and storage ring. The storage ring has an energy of 2 GeV, a circumference of about 388 m, an emittance of 5 nm rad, four 14 m-long straight sections and twelve 7 m-semi-long straight sections. The experimental hall is partly surrounded by a large hall, which enables the maximum length of the beamlines to be more than 80 m and gives scientific opportunities for carrying out spectroscopic experiments with extremely high resolution.

Sixty children aged between 1 and 23 months admitted to Queen Elizabeth Central Hospital in Blantyre, Malawi for diagnosis of acute lower respiratory tract infections (ALRI) were investigated for laboratory diagnosis of Pneumocystis carinii pneumonia (PCP) by indirect immunofluorescence assay on nasopharyngeal secretions. P. carinii was found in five of the 60 children. Three PCP cases had AIDS. The clinical presentation of children with PCP was of little diagnostic value and all the children were infants. Arterial oxygen saturation was significantly lower in PCP cases. Of the five PCP cases, four died, indicating that the marked hypoxaemia was associated with poor prognosis. These results indicate that an immunofluorescence assay on nasopharyngeal secretions could be used for first-line diagnosis of PCP in Africa.Indirect immunofluorescence assay of nasopharyngeal secretions from 60 children 1-23 months of age admitted to Queen Elizabeth Central Hospital in Blantyre, Malawi, with acute lower respiratory tract infections confirmed the presence of Pneumocystis carinii pneumonia (PCP) in 5 children. In Africa, diagnosis of PCP is generally based on clinical features, suspected immunosuppression, and chest radiography--all of which are limited in their capability to differentiate PCP from other pneumonias. 3 of the 5 infants diagnosed with PCP had AIDS. 14 children, including 8 of the 19 children with AIDS, died during hospitalization. 4 of the 5 children with PCP died, despite high-dose cotrimoxazole and oxygen therapy. In African children, PCP is often the first HIV-associated infection. More widespread use of the indirect immunofluorescence assay method is recommended for the rapid diagnosis of PCP cases in African children.

Solid-state oxide catalysts based on heteropoly compounds are three-dimensional (3D) crystalline materials constructed with polyoxoanion with a discrete uniform structure. Since the state of the anions directly affects their catalytic properties, controlling of discrete structure and elemental composition of the anions and 3D structure of the anion arrangement are primary factors in designing and developing heteropoly compound catalysts. The most prominent point of the heteropoly compound catalysts is homogeneity and uniformity of the catalytically active surface which is determined by the arrangement of polyoxoanions. Heteropoly compound catalysts are, therefore, considered as similar to homogeneous catalysts. This chapter introduces structural fundamentals of heteropoly compounds, followed by recent heterogeneous catalytic applications and new trends of catalytic materials synthesis based on heteropoly compounds.

Seedlings of the red mangrove, Rhizophora mangle L., were subjected to a variety of salinity, light, and plant growth regulator treatments to examine the influence of these factors on early development. Stem, leaf, and root growth were significantly enhanced in both low salinity seawater and under reduced intensities of solar radiation. Semi-quantitative analyses of GAs by enzyme-linked immunoabsorbant assays (ELISA) suggest that under these conditions the early 3/13 hydroxylation GA1 biosynthetic pathway is predominant in R. mangle. Concentrations of GA1 and GA19-like substances were highest in propagules exhibiting enhanced development. Attempts to identify the endogenous GAs by GC-MS were unsuccessful, most likely due to undetermined impurities present in mangroves. Exogenous applications of GA3 to R. mangle were moderately successful in alleviating shoot growth inhibitions observed at higher salinities and light levels. The role of gibberellins is discussed in terms of metabolic responses to the external environment and possible impacts upon the distribution of this species.

Sensitivity of the parameters of the dual-mode sorption (DMS) model on the pressure range, in which sorption of gases in polymers have been studied, was analyzed. Different “gas-polymer” systems were considered but the most detailed analysis was performed for sorption of argon and nitrogen in poly[5,5-difluoro-6,6-bis(trifluoromethyl)] norbornene and polysulfone. It was shown that the model parameters depend upon the range of gas pressure studied. Expanding of the pressure range (0-pi) results in an increase in the Langmuir adsorption capacity C′H and in reduction of Henry's law solubility coefficient kD and Langmuir affinity parameter b. These behaviors does not depend on a choice of an experimental apparatus or software and procedure of nonlinear least squares treatment of the data. As statistical analysis indicated, a systematic error of the measurement cannot call forth the observed dependencies of the model parameters. Different physical reasons of these behaviors were considered, among them: the pressure dependence of the affinity parameter, and the dilation of a polymer. The results obtained showed that although the DMS model, as a rule, gives an excellent fit of the experimental curves, and, hence, can be used as a form of compact storage of information on gas sorption in polymers, one should be careful in using it outside the pressure range in which its parameters have been determined. © 1996 John Wiley & Sons, Inc.

We investigated the effect of the pre-irradiation of a polymer target in vacuum, using a low-fluence laser pulse, on the synthesis efficiency of carbon cluster ions ejected by laser ablation. A polymer target was irradiated by two laser pulses. The first laser was used for the pre-irradiation, and the second laser was used for ablation. The masses of the ions in the ablation plume were analyzed by time-of-flight mass spectrometry. It was found that the synthesis efficiency of carbon cluster ions was enhanced by the pre-irradiation. The effects of the fluence of the pre-irradiation, the wavelengths of the lasers, and the interval between the oscillations of the two laser pulses on the enhancement of the cluster synthesis are reported.