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The lunar heat-flow ultra-wideband spectrometer operates over an extended frequency band from 300 MHz to 6.0 GHz. It is a direct-acquisition single-chain digital spectrometer measuring 1024 spectral channels over 6 GHz bandwidth with each channel bandwidth about 6 MHz. The LHR instrument is intended to characterize the near surface regolith thermal and dielectric properties in order to determine the local geothermal heat flux. It would also reveal subsurface thermal and dielectric property changes due to buried ice, dielectric materials like ilmenite, and bedrock. The wide spectral bandwidth is expected to provide up to 1 m deep brightness temperature measurements from as close as 5 cm penetration depth at higher frequency end of the spectra. Using information obtained at multiple frequency bands, the subsurface temperatures and dielectric properties can be reconstructed. The instrument is currently being developed at Jet Propulsion Laboratory in Pasadena, CA. The design includes a novel receiver architecture allowing a single chain design for the ultra-wideband channelized spectral operation for enabling the science objectives of the instrument. The lab-bench demonstration of the lunar spectro-radiometer has been performed including the calibration testing. The environmental testing will be further conducted before proceeding with the flight model. The final flight version of the spectro-radiometer instrument is expected to have light weight, low-power and small-size suitable for a deployment into a lunar rover or lander.

In this work, a novel 670-GHz integrated direct-detection receiver using 25-nm InP HEMT technology is presented. This is the first demonstration of an integrated direct-detection radiometer architecture at these frequencies. The receiver exhibits a noise figure of 11.4 dB with a total dc power consumption of 0.25 W. The integrated receiver measures only 0.8 cm × 1.3 cm × 4.8 cm (0.3” × 0.5” × 1.9”). These results show that transistor-based direct-detection receivers are a viable technology for submillimeter-wave applications, with low SWaP with no compromise in performance.

In this letter, a novel 1/f noise mitigation technique is presented to improve the receiver 1/f noise performance of a 670 GHz receiver. The time-domain 1/f noise corrected samples are compared with the samples obtained without the correction. The spectral-domain analysis shows that the 1/f noise mitigation method improves the receiver noise performance by 19 dB in the receiver under test. The presented 1/f noise mitigation technique can be applied to any direct-detection receiver in the terahertz frequency range.

Calibration plays an important role in improving the accuracy of the microwave and millimeter-wave radiometric measurements. Several calibration techniques have been used in radiometers including external calibration targets, vicarious sources, and internal calibrators such as noise diodes or matched reference load. A new calibration technique based on deep learning has recently been developed to calibrate microwave and millimeter-wave radiometers. The deep-learning calibrator has been previously demonstrated on a computer noise-wave modeled Dicke-switching radiometer. This article applies the new deep-learning calibration technique for the calibration of the high-frequency airborne microwave and millimeter-wave radiometer (HAMMR) instrument. A deep-learning neural network model is built to calibrate the 2014 West Coast Flight Campaign antenna temperature measurements of the HAMMR. The deep-learning calibrator antenna temperature estimates are obtained from the radiometric measurements. The deep-learning calibration results are compared with the existing conventional calibration techniques used in HAMMR 2014 field campaign. The results have shown that the deep-learning calibrator is in agreement with the conventional calibration techniques. In this article, it is demonstrated that the deep-learning calibrator can be employed for calibrating the radiometers with high accuracy.

The high-frequency airborne microwave and millimeter-wave radiometer (HAMMR) is a cross-track scanning airborne radiometer instrument with 25 channels from 18.7 to 183.3 GHz. HAMMR includes: low-frequency microwave channels at 18.7, 23.8, and 34.0 GHz at two linear-orthogonal polarizations; high-frequency millimeter-wave channels at 90, 130 and 168 GHz; and millimeter-wave sounding channels consisting of eight channels near the 118.75 GHz oxygen absorption line for temperature profiling and eight additional channels near the 183.31 GHz water vapor absorption line for water vapor profiling. HAMMR was deployed on a twin otter aircraft for a west coast flight campaign (WCFC) from November 4–17, 2014. During the WCFC, HAMMR collected radiometric observations for more than 53.5 h under diverse atmospheric conditions, including clear sky, scattered and dense clouds, as well as over a variety of surface types, including coastal ocean areas, inland water and land. These measurements provide a comprehensive dataset to validate the instrument.

Deep learning artificial neural network techniques can be applied for on-orbit calibration of microwave and millimeter-wave radiometer spaceborne instruments, including those for small satellites. The noise-wave model has been employed for noise characterization and validation of the proposed deep learning calibration technique for a synthetically generated Dicke-switching radiometer. The developed deep learning neural network radiometer calibrator produces high accuracy estimates of antenna temperatures from the measurements of radiometer output voltage and thermistor readings. Tests with noise-free and noisy samples of the developed model have shown that the proposed calibration method does not add any significant noise to the radiometer calibration. The performance of the proposed method does not degrade with increased nonlinearity for a radiometer, while nonlinearity is a challenging issue for conventional calibration techniques. The deep learning calibration model learns the radiometer noise characteristics from radiometer prelaunch measurements during thermal vacuum chamber testing. The neural network calibrator proposed in this paper has self-learning capability during the on-orbit operation of a radiometer that can be used to improve the performance of on-orbit calibration. The proposed technique is demonstrated by comparing the residual uncertainty of the deep learning calibration with the theoretical value. No numerical study is presented to compare the performance with conventional calibration techniques. The new method may be solely applied to calibrate the radiometer or applied along with conventional calibration techniques.

Background: To research the perioperative significance of the simple laboratory test values on differentiating complicated acute appendicitis. Methods: The medical records of 216 acute appendicitis patients were examined retrospectively. Patients were divided into two groups according to pathological results (non-complicated (n=157) and complicated (n=59)). The demographic and clinical data, laboratory findings, length of hospital stay, and pathological results were compared between the two groups. Receiver operating characteristics (ROC) curves were performed to analyze the optimal cutoff value of numerical variables which were significantly differed between the group comparisons. Results: The preoperative data were similar in two groups except for age. The length of hospital stay (LOHS) was longer and total/direct bilirubin levels higher in the complicated group (p=0.002, p=0.002, and p=0.002, respectively. The lymphocyte level and amylase level were lower in the complicated group (p=0.02 and p=0.004, respectively). ROC curve analysis showed a cutoff values as follows: total bilirubin ≥0.89 mg/dL, direct bilirubin ≥0.43 mg/dL, lymphocyte≤1.63%, and amylase ≤46.5 U/L. Conclusion: Preoperative higher total and direct bilirubin levels are able to predict complicated appendicitis. Preoperative higher serum amylase levels should not have a place in the differential diagnosis of complicated appendicitis. This means that if serum amylase is elevated in a patient with doubted acute appendicitis, it does not suggest acute complicated appendicitis.

A new ultra-wide P/L-band radiometer instrument has been developed at the Jet Propulsion Laboratory for polar ocean salinity and seasonal sea-ice thickness measurements. The Arctic field campaign performed with the instrument deployed on the US Coast Guard Cutter Healy from September 13, 2018 to October 20, 2018. A new calibration strategy is developed for the ultra-wide band instrument to minimize the mismatch related effects. A noise-wave model is built to analyze and validate the instrument behavior for the calibration. The calibration strategy is analyzed using the results from the cruise campaign. Sea-ice thickness and sea surface salinity are presented in two other companion papers.

The Tropospheric Water and Cloud ICE (TWICE) millimeter and sub-millimeter radiometer instrument is being developed to enable global observations of upper tropospheric/lower-stratospheric water vapor and ice particle size distribution in clouds. Global observations using the TWICE instrument are critically needed to reduce uncertainties in weather and climate models. A low-noise, power-efficient command and data handling (C&DH) subsystem has been designed and tested to control TWICE data acquisition and other subsystems. Considering the limited power resources available on such platforms, a highly-efficient power regulation board has been designed to minimize power losses and reduce system noise. Furthermore, heavy-ion radiation testing has been performed for some critical commercial-off-the-shelf components to analyze radiation tolerance in low-Earth orbit. The C&DH prototype board meets the functional, noise and size, weight and power (SWaP) requirements for deployment on a 6U -Class satellite.

Fly ash (FA) from coal burning power plants is generally used for biosolids stabilization to reduce numbers of pathogens and availabilities of heavy metals contained in biosolids. The objective of this study was to determine the suitability of sugar beet lime (SBL) from sugar beet processing factories as fly ash substitute. Post-harvest soil samples were employed in a 180 d incubation study for each of two year field experiments. A first order logistic model was used to estimate sizes of labile and delayed logistic C pools. All treatments with one exception significantly (P

A two year field experiment was conducted in field conditions using wheat (Triticum aestivum ssp. vulgare L. cv. Bezostaja) as the test plant for the evaluation of phosphate solubilizing (+PS) microorganisms. Bacterial strains significantly (P < 0.05) increased plant biomass (by 13 to 36%) without plant P enrichment. Only Bacillus sp. #189 significantly (P < 0.05) raised plant P-content, biomass and rhizosphere soil Olsen P at Zadoks Scale 62 simultaneously. Inoculations variably increased plant potassium (K-), magnesium (Mg-), zinc (Zn-), and managenese (Mn-) contents at harvest (Zadoks 92) but not earlier (Zadoks 31 and 61). The enrichment of the inoculated plants with nutrients other than P indicates the presence of alternative plant growth promoting mechanisms. This study showed that promising phosphate solubilizing microorganisms could increase not only the P content of the plants, but also the soil available P in rhizosphere transiently.

Radiation effects analysis is essential to improve reliability for space missions. The number of small satellite and CubeSat missions has increased significantly in recent years. Compared to traditional larger satellite missions, CubeSats are designed at lower cost and with shorter development cycles. The reliability of CubeSats and small satellites in on-orbit radiation environments needs to be ensured for mission success. In this study, single event effect analysis has been performed for a 6U-Class satellite instrument in low Earth orbit to improve its on-orbit reliability. Critical commercial off-the-shelf parts of the Command and Data Handling Subsystem of a 6U-Class satellite instrument have been tested under heavy-ion radiation at the Texas A&M University Cyclotron Institute Radiation Effects Facility. SEE characteristics have been tested and analyzed for analog-to-digital data converters, voltage regulators, and current sensing and voltage monitoring devices. Device- and system-level risk analyses have been performed for the Command and Data Handling electronics based on the results of heavy-ion radiation testing. System-level mitigation techniques have been studied to minimize the effects of SEEs on electronic systems for deployment on 6U-Class satellites in low Earth orbit.

Global measurements of upper tropospheric/lower-stratospheric water vapor and ice particle size distribution in clouds are critically needed to reduce uncertainties in global weather and climate models. To address this need, the conically scanning Tropospheric Water and Cloud ICE (TWICE) millimeter and submillimeter radiometer instrument is being developed. A low-noise, power-efficient command and data handling (C&DH) subsystem has been designed to control TWICE data acquisition and other subsystems. The C&DH prototype board meets functional, noise and size, weight and power (SWaP) requirements for deployment in a 6U-class satellite. Considering the limited power resources available on such platforms, a highly-efficient power regulation board has been designed to minimize power losses and reduce system noise. Furthermore, all of the components have been tested for radiation tolerance in low-Earth orbit.

Global measurements of cloud ice particle size, total ice water content and water vapor content in the upper troposphere are critically needed to improve knowledge of the role of ice clouds in Earth's climate, precipitation and cloud processes. Such observations will enable improvement in cloud and moisture simulations in global climate models as well as precipitation forecasts on a global basis. Measurements at a range of frequencies in the millimeter- and submillimeter-wave frequency range provide sensitivity to ice particle size distribution in the range of tens to hundreds of micrometers. To perform this measurement on a global basis, a new millimeter- and submillimeter-wave instrument is currently under development with suitable mass, power and volume to be deployed on 6U-Class nanosatellites. To achieve miniaturized receivers in this frequency range, InP MMIC technology has been scaled to 25-nm gate length transistors, enabling demonstration of low-noise amplifiers with sufficient gain at frequencies up to 1 THz. This technology is being applied to develop direct-detection submillimeter-wave receivers at 240 GHz, 310 GHz and 670 GHz. InP MMIC technology has also enabled multipliers for local oscillators and subharmonic mixers for temperature and humidity sounding channels near atmospheric absorption lines at 118.75, 183.31 and 380.20 GHz.

Global measurements of ice in clouds, both the amount and particle size distribution, are critically needed to reduce uncertainties in global climate models. The retrieval of this information is best achieved with a range of receiver channels across the submillimeter wave range. Advancement of low noise Indium Phosphide (InP) MMIC amplifier technology enabled us to develop miniature submillimeter-wave receivers for a CubeSat scale instrument that achieves 6 km spatial resolution. The heritage of InP MMICs includes continuous operation for four years in the PLANCK Low Frequency Instrument and providing world-record sensitivity with high reliability in several airborne instruments. We have developed a set of InP MMICs for receivers at 240, 310, 380 and 670 GHz with significantly lower noise than previously reported. The noise temperature is NT=450 K at 240 GHz, NT=550K at 310 GHz and NT=650 K at 380 GHz. The 670 GHz LNAs provide a NT of 2400 K. These channels are complemented by the previously-developed and airborne-proven 183 and 118 GHz MMIC receivers that were tested to TRL 6.

Many phosphate solubilizing microorganisms (PSM) require external pyrroloquinoline quinone (PQQ) for strong phosphorus (P) solubilization in vitro. The objective of this study was to isolate efficient and PQQ-independent PSM. A total of 21 PSM were isolated from the rhizosphere soil of wheat and maize grown in the pots. Acinetobacter strains were the only PQQ-independent and most effective solubilizers of tricalcium phosphate containing agar. The mean P dissolved in liquid cultures of Acinetobacter strains in a 5-day incubation ranged from 167 to 888 μg/ml P. The pH dropped to below 4.7 from 7.8 in six isolates, which produced gluconic acid in concentrations ranging between 27.5 and 37.5 mM. There was a linear regression between soluble P and gluconic acid concentrations in the bacterial cultures (P

Fly ash and biosolid wastes can be mixed and applied to soil as a means of disposal. A significant decline in soil respiration following waste application indicates restricted activities of functional microbial populations. Weathering decreases salinity and neutralizes alkalinity in fly ash, but there is little information on the effects of unweathered fly ash and biosolid mixtures on soil carbon (C) mineralization. The objective of this study was to determine the effects of a weathered fly ash–limestone scrubber residue (LSR) mixed with an aerobically digested biosolid on soil respiration in a laboratory incubation study. Biosolids significantly increased carbon dioxide (CO2) production (p < 0.05), but up to 6.75% (w/w) fly ash did not. Mean total C mineralization was 770 mg CO2‐C kg−1 soil in the control and 3,810 mg CO2‐C kg−1 soil in the 6.75% (w/w) biosolid treatment. Fly ash with neutral pH and low salinity appears unlikely to affect soil and biosolid C mineralization.

Micronutrient deficiency and malnutrition in humans are severe problems in many developing countries, particularly in areas with calcareous soils. There is almost no information on whether inoculation with plant growth-promoting Azospirillum and/or Trichoderma can help to reduce this problem by increasing the mineral concentration of the seeds. Field experiments were conducted in Tokat (Turkey) in 2001-2002 to determine whether inoculation with Azospirillum brasilense, Trichoderma harzianum, sole or in combination, and/or the application of P fertilizers can enhance micronutrient concentrations of field-grown bean (Phaseolus vulgaris) and wheat (Triticum aestivum). In beans, Azospirillum inoculation combined with P fertilization significantly (p < 0.05) increased seed concentrations of Mn, Zn, and Cu, from 8.8, 22.6, and 7.0 mg kg -1 in the control to 10.3, 28.3, and 11.0 mg kg -1 , respectively. Trichoderma inoculation alone significantly (p < 0.05) reduced the concentrations of Fe, Mn, Zn, and Cu and the cumulative plant uptake of Fe and Zn in 45-day-old bean plants. However, it significantly (p < 0.05) increased bean-seed Cu content and accumulation. The double inoculation resulted in significantly (p < 0.05) higher micronutrient concentrations than Trichoderma inoculation alone in 45-day-old plants. In contrast to beans, the effects of microbial inoculations were less in wheat. However, dual inoculation significantly (p < 0.05) increased Zn content by 45% and Zn accumulation by 40% above the uninoculated control. Inoculation with plant growth-promoting microorganisms appears to be a promising strategy to combat micronutrient deficiencies.

A plant growth-promoting rhizobacterium (Azospirillum brasilense Sp7) and a bio-control fungus, which can solubilize insoluble phosphorus (Trichoderma harzianum Rifai 1295-22), were evaluated for their single and combined effects on dry bean (Phaseolus vulgaris) and wheat (Triticum aestivum L.) grown in soil. A pot experiment with bean and a field experiment with both bean and wheat were established. In contrast to single inoculation of Trichoderma, the single inoculation of Azospirillum and the double inoculation did not significantly (P >0.05) increase nodule numbers and nodule mass at 45 days after planting in pot grown beans. However, the Azospirillum inoculation with supplementary phosphorus significantly (P 0.05) differences among the inoculation treatments for plant dry weight, total plant nitrogen, and total plant phosphorus at 45 days after planting in both pot and field experiments with bean. However, the combined inoculation and rock phosphate application at 1 Mg ha−1 significantly (P 0.05). The combined inoculation improves many plant and yield parameters and, therefore, has some advantages over single inoculation provided that rock phosphate was supplied at an amount not exceeding 1 Mg ha−1. Higher rock phosphate application rates decreased many plant and yield parameters in our study.

The effect of cobs on radar backscatter from a mature corn canopy is considered. In the past, a number of papers have modeled the backscattering properties of corn plants when the cobs are not present. It has been shown by O'Neill et al. [1] that the cob can constitute as much as one third of the total biomass of a mature corn plant. The position of the cob close to the stalk and the lack of knowledge of its dielectric properties make it difficult to model. These difficulties have been overcome with the aid of advanced numerical analysis tools and new biophysical measurements of the corn.

Summary form only given. This paper presents the design, construction and results of measurements of a dual polarized L- band antenna for the NASA Combined Radiometer and Radar System. The radiometer band covers 1.400 -1.427 GHz. and the radar band 1.250 to 1.350 GHz. The focus of this paper is on the radiometer band. The antenna is designed to replace the 48 inch diameter truck-mounted paraboloidal dish used in NASA remote sensing applications because of its excessive loss. It was found that changes of the ambient temperature produced fluctuations in the antenna noise temperature which reduced the accuracy of the radiometer calibration. These fluctuations are caused by the temperature dependent Ohmic loss in the antenna structure, the externally mounted cable connecting the Newtonian feed to the radiometer and in the patch used for the feed. Therefore the principal design goal for the new antenna was to eliminate the need for the cable and the patch and to reduce any additional loss without a degradation of its electrical performance and without increasing its size and weight. A configuration that obviates the need for an external feed-to-radiometer cable connection is a Cassegrain antenna. Its additional advantage is that the feed structure can be designed to have a lower loss than the patch used in the Newtonian feed of the old antenna. Since classic Cassegrain antennas generally require reflectors with diameters of at least 30 wavelengths designing an antenna in a Cassegrain configuration incorporating a reflector with a diameter of only 5 to 6 wavelength represented a real challenge. This challenge was met with the design that employs a novel low loss dielectric (Rexolite) conical support structure for the subreflector. The cone diameter decreases linearly from its base at the apex to the subreflector. The novel feature in this design is that in addition to supporting the subreflector the cone also serves as a dielectric waveguide that illuminates the subreflector. The mechanism for this is the wave within the cone that travels from the apex of the paraboloid toward the subreflector and illuminates it by a partial leakage into the surrounding space. The resulting efficiency is appropriate for a truckmounted antenna system. The input at the apex of the paraboloid employs a circular waveguide that supports two orthogonal TE11 modes thus providing the necessary dual polarization. As confirmed by simulations and measurements the gain and side lobe levels of the new low loss antenna are comparable to those of the old antenna.

The objective of this paper is to discuss the performance of a new L-Band, truck-mounted radiometer antenna. This new low loss antenna has been designed to increase the calibration stability of the ComRAD radiometer system. ComRAD is a dual polarized combined radar radiometer system operating as a radar at 1.3 GHz and as a radiometer at 1.413 GHz. It utilizes the same antenna for both frequencies. ComRAD is used to develop algorithms for the sensing of soil moisture in the presence of vegetation. The system is presently being employed to monitor agricultural crops over the growing cycle in preparation for the upcoming SMAP (Soil Moisture Active Passive) satellite mission.