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Decline in global carnivore populations has led to increased demand for assessment of carnivore densities in understudied habitats. Spatial capture–recapture (SCR) is used increasingly to estimate species densities, where individuals are often identi- fied from their unique pelage patterns. However, uncertainty in bilateral individual identification can lead to the omission of capture data and reduce the precision of results. The recent development of the two-flank spatial partial identity model (SPIM) offers a cost-effective approach, which can reduce uncertainty in individual identity assignment and provide robust density estimates. We conducted camera trap surveys annually between 2016 and 2018 in Kasungu National Park, Malawi, a primary miombo woodland and a habitat lacking baseline data on carnivore den- sities. We used SPIM to estimate density for leopard (Panthera pardus) and spotted hyaena (Crocuta crocuta) and compared estimates with conventional SCR methods. Density estimates were low across survey years, when compared to estimates from sub-Saharan Africa, for both leopard (1.9 0.19 SD adults/100 km2) and spotted hyaena (1.15 0.42 SD adults/100 km2). Estimates from SPIM improved precision compared with analytical alternatives. Lion (Panthera leo) and wild dog (Lycaon pictus) were absent from the 2016 survey, but lone dispersers were recorded in 2017 and 2018, and both species appear limited to transient individuals from within the wider transfrontier conservation area. Low densities may reflect low car- rying capacity in miombo woodlands or be a result of reduced prey availability from intensive poaching. We provide the first leopard density estimates from Malawi and a miombo woodland habitat, whilst demonstrating that SPIM is benefi- cial for density estimation in surveys where only one camera trap per location is deployed. The low density of large carnivores requires urgent management to reduce the loss of the carnivore guild in Kasungu National Park and across the wider transfrontier landscape.

Sr/Ca ratios recorded in the aragonite skeleton of massive coral colonies are commonly used to reconstruct seasonal‐ to centennial‐scale variability in sea surface temperature (SST). While the Sr/Ca paleothermometer is robust in individual colonies, Sr/Ca‐SST relationships between colonies vary, leading to questions regarding the utility of the proxy. We present biweekly‐resolution calibrations of Sr/Ca from five Porites spp. corals to satellite SST across 10° of latitude in the Red Sea to evaluate the Sr/Ca proxy across both spatial and temporal scales. SST is significantly correlated with coral Sr/Ca at each site, accounting for 69–84% of Sr/Ca variability (P ≪ 0.01). Intercolony variability in Sr/Ca‐SST sensitivities reveals a latitudinal trend, where calibration slopes become shallower with increasing mean annual temperature. Mean annual temperature is strongly correlated with the biweekly‐resolution calibration slopes across five Red Sea sites (r2 = 0.88, P = 0.05), while also correlating significantly to Sr/Ca‐SST slopes for 33 Porites corals from across the entire Indo‐Pacific region (r2 = 0.26, P < 0.01). Although interannual summer, winter, and mean annual calibrations for individual Red Sea colonies are inconsistently robust, combined multicoral calibrations are significant at summer (r2 = 0.53, P ≪ 0.01), winter (r2 = 0.62, P ≪ 0.01), and mean annual time scales (r2 = 0.79, P ≪ 0.01). Our multicoral, multisite study indicates that the Sr/Ca paleothermometer is accurate across both temporal and spatial scales in the Red Sea and also potentially explains for the first time variability in Sr/Ca‐SST calibration slopes across the Indo‐Pacific region. Our study provides strong evidence supporting the robustness of the coral Sr/Ca proxy for examining seasonal to multicentury variability in global climate phenomena. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Published version

A redetermination of the argon mole fraction in air has been undertaken in two samples of dried natural air using mass spectrometric analysis with reference to a suite of gravimetrically prepared synthetic dry air mixtures. The resulting measurement of the argon mole fraction was 9.332 mmol mol −1 with a combined standard uncertainty of 3 µmol mol −1 . This is significantly different from the value, 9.17 mmol mol −1 , conventionally employed in the CIPM formula for the determination of the density of moist air during mass standard comparisons. Using the presently reported argon mole fraction value in the CIPM formula rather than the conventional value removes the recently identified discrepancy between the two methods of determining the density of moist air during mass standard comparisons: the CIPM formula method and the air buoyancy artefacts method. Nitrogen, oxygen and carbon dioxide mole fractions in the dry air samples were obtained simultaneously.

We have determined the inhomogeneities in the density of prototype STEP test masses made from HIPed beryllium and niobium using the hydrostatic weighing method developed at BIPM. 13 samples are taken from a HIPed beryllium rod (approximately 140 mm long by 90 mm) and 24 samples from a niobium rod (approximately 225 mm long by 45 mm). The maximum relative difference of density is found to be approximately 240 ppm in the beryllium samples and 60 ppm in the niobium samples. Assuming that there is a 10 g helium bubble at 250 mm from the test masses acting as a source, these inhomogeneities of density would produce a disturbance of Δa/a = (1.1±0.7)×10-18 in a beryllium outer test mass and (5.1±0.5)×10-20 in a niobium inner test mass, in the STEP experiment. The inhomogeneities of density in the HIPed beryllium rod appear to be too large for the STEP experiment, which aims at a sensitivity of one part in 1018. We suggest that it is important to find a way to fabricate more homogeneous HIPed beryllium.

Changes in the display of a mass balance caused by the effect of the earth's magnetic field were measured at the Korea Research Institute of Standards and Science (KRISS) using the Bureau International des Poids et Mesures (BIPM) susceptometer operating in a Helmholtz coil system. The experimental results concerning this effect generally agreed with the theoretical predictions within the uncertainty of the balance (about 1 µg). A few anomalies were noted and are discussed in the text.

The volume magnetic susceptibility of moist air ?m(ma) is needed to correct the results of certain experiments to vacuum conditions. This paper derives an appropriate equation for ?m(ma) for which pressure, temperature, relative humidity, and carbon dioxide content are variable parameters. The derived equation also depends sensitively on the molar susceptibility of oxygen, for which the handbook values are inconsistent by about 1.4%. The equation resolves this discrepancy in part.

Small rare‐earth magnets have remarkable properties that can be exploited in the construction of simple measuring devices. Examples are a torsion pendulum that measures the earth’s horizontal magnetic field and a gravimetric pendulum that responds to the small susceptibilities of various ‘‘nonmagnetic’’ materials. These preliminary demonstrations lead to the design of a practical device for measuring the susceptibilities of feebly magnetic metals in low magnetic fields. Our laboratory has used this last method to determine relatively small magnetic susceptibilities, down to 0.0003, to an uncertainty of less than 20%. A convenient feature of our apparatus is that calibration by a susceptibility standard is not required.

The results of international comparisons of density measurements are reported. Participants include the national laboratories of Australia, the Federal Republic of Germany, Italy, Japan, the UK, and the United States, as well as the Bureau International des Poids et Mesures. The comparisons involve hydrostatic density determinations of samples made of single-crystal silicon and samples made of stainless steel. Agreement among laboratories is generally better for samples of silicon than for samples of stainless steel. Overall discrepancies do not, however, appear to be serious with respect to scientific and metrological needs.

The height of the centre of mass above the base of a 1 kg artefact can be located easily within a precision of several micrometres using a simple 'weighbridge'. Analysis of the device, its realization and performance are presented. The method has applications in high-precision mass metrology and certain gravitational experiments.

1. An RVU system can forecast staffing needs for a busy ambulatory ophthalmology clinic. 2. The average amount of time needed for basic ophthalmic screening is 15 minutes. 3. Further studies should be conducted of infrequent tasks and for indirect care before an RVU system can be accurately used.

The suitability of a commercially available, compressed-gas-insulated, high voltage capacitor for precise measurement of ac voltages has been examined by national laboratories in the U.S.A. and Canada. The voltage, temperature, and pressure dependences and the mechanical stability of the capacitor were determined. It was found that by taking proper precautions the device is competitive with other methods. As a result of this research, it was also found that high voltage capacitance measurements at the two laboratories involved are in agreement.

The influence of genetic factors on the manifestations of disease associated with infection with Schistosoma mansoni (portal hypertension, liver granulomas, hepatosplenomegaly) and their modulation were studied in inbred strains of mice. Three groups were identified according to the degree of portal hypertension: high (portal venous pressure, 19.1 cm H2O: DBA/1J), intermediate (8.9-13.4 cm H2O; BALB/cJ, DBA/2J, CBA/CaJ, C3H/HeJ, and BUB/BnJ), and low responders (6.1 cm H2O; C57BL/6J). Granuloma size, organomegaly, and portal venous pressure were strain dependent and not H-2 dependent and were determined by more than one gene. Studies of schistosomiasis in the F1 generation of high and low responders indicated that more than one gene is involved. Modulation of portal venous pressure between eight and 20 weeks of infection occurred in C57BL/6J but not in BALB/cJ mice and was transferable with immune lymphoid cells. These data indicate that disease associated with infection with S. mansoni and its modulation in mice are influenced by the genetic (non-H-2) background of the host and dependent in part on cell-mediated immunity.

SUMMARYMicrofilariae of Brugia malayi were obtained from the peritoneal cavities of infected gerbils and were then injected intravenously into mice. A sub-periodic, nocturnal microfilaraemia was produced. The level of microfilaraemia was proportional to the number of parasites injected, with approximately 1–3% of microfilariae being found in the peripheral circulation. The duration of microfilaraemia was proportional to the number of parasites injected; it subsided by 30 days after injection of 104 microfilariae but was still present at a low level 120 days after injection of 2 × 105 microfilariae. A transient splenomegaly developed after injection of microfilariae. Histopathological examination revealed large numbers of microfilariae free in the lumens of pulmonary small blood vessels and without any accompanying inflammatory reaction. Lesser numbers of microfilariae were seen in the cardiac blood and hepatic and renal blood vessels for the first few days after injection. There was cellular proliferation in the splenic white pulp and vascular congestion of the red pulp. Microfilariae labelled with 51Cr were injected intravenously; 57% of radioactivity was found in the lungs, 8·5% in the liver and 2·9% in the spleen. Mice developed immediate hypersensitivity reactions to B. malayi antigen by 4 weeks after injection, but Arthus and delayed hypersensitivity reactions were not seen at any time. When mice which had been injected 5 months previously were challenged with a 2nd injection of microfilariae, there was an accelerated clearance of parasites over 2 weeks and a marked peripheral blood eosinophilia developed. In contrast with natural infections, in which the continuous production of microfilariae complicates assessment, this model provides a system in which factors controlling the circulation of microfilariae in the bloodstream can be studied independently.

Tensile stress-strain curves are reported for aluminum single and bicrystal specimens. Isoaxial bicrystal specimens were used with one crystal rotated 45° about the stress axis with respect to the other. The axial orientations were chosen so that one, two, four, six, or eight slip systems were initially equally favored. The 45° grain boundary did not raise the stress-strain curve of the bicrystal above that of the corresponding single crystal if two or more slip planes were initially equally favored.

最適化の三方法すなわち線形計画法 (linear programming, LP), 動的計画法 (dynamic programming, DP), 最大原理 (maximum principle, MP) の基本的原理について図解例と計算例をあげ解説する。

A new technique has been developed by which naturally and anodically formed aluminum oxide produced on single‐crystal specimens has been studied in the electron microscope. The low‐temperature amorphous oxide grown by the transport of cations was smooth at the metal‐oxide interface. However, the oxide‐oxygen interface exhibited topography on certain crystal orientations. A high‐temperature crystalline oxide was found to grow by the transport of anions. Epitaxial growth was observed on several orientations. The anisotropy of oxide thickness which occurred at elevated temperatures is discussed.The above results are considered in terms of the structure of the metal‐oxide interface.

Species of Pseudomonas isolated from soil could utilize m- or p-xylene as the sole carbon source. The respective toluic acids of the xylenes were isolated from growth media and from cells suspended in buffer. Cells grown on either hydrocarbon were capable of "meta" type cleavage of catechol and the methylcatechols. A compound whose properties were consistent with the structure of 2-hydroxy-5-methylmuconic semialdehyde was produced when cell-free extracts of p-xylene-grown cells were confronted with 4-methylcatechol. This muconic semialdehyde was present in the growth medium of p-xylene-grown cells and in buffer suspensions of these cells confronted with p-xylene. Paraxylene-grown cells oxidized p-chlorotoluene and 4-chloro-catechol to a compound with a spectrum similar to those of "meta" cleavage products. Chemical isolations and manometric data are consistent with a pathway for the oxidative metabolism of p-xylene which includes p-methylbenzyl alcohol, p-tolualdehyde, p-toluic acid, 4-methylcatechol, and 2-hydroxy-5-methylmuconic semialdehyde.

Shock‐induced phase transformations in iron have been investigated in the temperature range 78° to 1158°K. The pressure for transformation over this temperature range has been determined by a technique that depends on microstructural changes associated with a phase transformation. A discontinuity in the temperature‐pressure relationship was observed at 115 kbars and 775°K. Two distinct transformation microstructures were observed. It is postulated that the results obtained above 775°K are due to the expected transformation from alpha iron to gamma iron whereas the results below 775°K are related to a transformation from alpha iron to a presently undetermined new phase.

A circuit is presented that makes use of low frequency square waves for exciting resistance bridges, detecting their departure from balance, and providing an output voltage for measurement or control purposes. Applications in several areas of precision metrology have been found.

An outbreak of amikacin-resistant Enterobacteriaceae (KES) occurred in the Intensive Care Nursery (ICN) of the Louisville General Hospital from January 1978 through March 1978. Epidemic disease and an increased colonization rate in newborn infants due to amikacin-resistant microorganisms has not been documented previously. Three of the 11 neonates died. The organisms isolated were resistant to amikacin and two experimental aminoglycosides, sissomicin and netilmicin. The outbreak was contained following institution of several control measures, including pharyngeal inoculation of an experimental strain of alpha streptococcus in four infants.

Optimal preservation of renal and ureteral structure and function is attempted by maintenance of renal circulation during heart-beating cadaver nephrectomy. Modifications of Ackermann's en bloc procedure for removal of cadaver kidneys are suggested to adapt this procedure to the heart-beating cadaver situation.

The visualization of vegetations by M-mode echocardiography in patients with infective endocarditis has been suggested to imply a poor prognosis regarding the development of major systemic emboli, congestive heart failure and the need for early surgical intervention. The question of using the finding of vegetations by echocardiography as an indication for surgery is controversial. To answer this question, 30 patients with the clinical diagnosis of endocarditis were studied by echocardiography. In 17 of the 30 (57 per cent) vegetations were present (aortic eight, mitral four, both mitral and aortic five), whereas in 13 (43 per cent) no vegetations were visualized. Infecting organisms were similar in each group; Streptococcus viridans being the most common. The patients with echocardiographically demonstrable vegetations had a higher incidence of congestive heart failure compared to the patients without (14 of 17 versus six of 13, p less than 0.05), major emboli (eight of 17 versus two of 13, p = NS) and need for valve surgery (17 of 17 versus two of 13, p less than 0.001). Mortality was not significantly different in the two groups (six of 17 versus three of 13, p = NS). Urgent or emergency surgery was required in 16 of 17 patients with vegetations. Thus, the demonstration of vegetations by echocardiography identified a subset of patients with more severe disease in whom early operative intervention was required.

Pollution Prevention Consultants, Inc. (PPC) is using existing fluidised-bed gasification technology to develope a synthetic fuel from wood process whereby the synfuel product is acceptable for use in a standard methanol-producing plant. The basis for this technology is the operation of a pilot plant and a demonstration plant which have provided a database in both the gasification and combustion modes. A brief description of the pilot plant units preceeds the discussion of the synthetic fuel from wood process.

Simple thermodynamic arguments1,2 lead one to believe that in the presence of a counterflow velocity the transition from He II to He I should occur at temperatures somewhat lower than the λ temperature at saturated vapor pressure. The most convenient method of generating a counterflow velocity is to apply a heat flux Q in an otherwise undisturbed column of He II. However, the application of a heat current has certain concomitant effects which have not been included in the theoretical studies so far and which may alter the existing results both qualitatively and quantitatively. First, when a heat flux is present there is invariably a temperature gradient, and second, for moderate Q values the thermal resistance is in large part due to a tangled mass of vortex lines in the fluid. Unfortunately, there does not appear to be any simple way to modify the existing theory to take account of these effects.