Effects of magnetite on high-frequency ground-penetrating radar

Large concentrations of magnetite in sedimentary deposits and soils with igneous parent material have been reported to affect geophysical sensor performance. We have undertaken the first systematic experimental effort to understand the effects of magnetite for ground-penetrating radar (GPR) characterization of the shallow subsurface. Laboratory experiments were conducted to study how homogeneous magnetite-sand mixtures and magnetite concentrated in layers affect the propagation behavior (velocity, attenuation) of high-frequency GPR waves and the reflection characteristics of a buried target. Important observations were that magnetite had a strong effect on signal velocity and reflection, at magnitudes comparable to what has been observed in small-scale laboratory experiments that measured electromagnetic properties of magnetite-silica mixtures. Magnetite also altered signal attenuation and affected the reflection characteristics of buried targets. Our results indicated important implications for several fields, including land mine detection, Martian exploration, engineering, and moisture mapping using satellite remote sensing and radiometers.

Nutritional risk of cancer patients receiving chemotherapy in the ambulatory care setting : a prospective study

Background Cancer itself can alter the metabolic and physiologic of the body's nutritional needs. As a result, some patients experience some degree of weight loss before the start of the treatment. Aim The aim of the study was to determine at which chemotherapy treatment cycle patients with cancer begin to exhibit signs and symptoms of malnutrition. Methods A prospective descriptive correlational design was used to assess the nutritional risk of 111 patients with cancer receiving chemotherapy in the ambulatory setting. The data were collected by using a nutritional screening tool. Findings The prevalence of malnutrition risk was 45% in patients undergoing the first cycle of chemotherapy. Patients who received the first three cycles of chemotherapy were 2.62 times more likely to develop malnutrition than those who received seven or more cycles. The risk of developing malnutrition varies depending on the type of cancer, the types of chemotherapy regime, the number of chemotherapy cycles, body mass index and the stage of cancer. Conclusion The study found about half of the patients had developed signs and symptoms of nutritional risk at cycle one. Hence, nutritional support may be required even before the start of chemotherapy.

Localization and place recognition using an ultra-wide band (UWB) radar

This paper presents an approach to mobile robot localization, place recognition and loop closure using a monostatic ultra-wide band (UWB) radar system. The UWB radar is a time-of-flight based range measurement sensor that transmits short pulses and receives reflected waves from objects in the environment. The main idea of the poposed localization method is to treat the received waveform as a signature of place. The resulting echo waveform is very complex and highly depends on the position of the sensor with respect to surrounding objects. On the other hand, the sensor receives similar waveforms from the same positions.Moreover, the directional characteristics of dipole antenna is almost omnidirectional. Therefore, we can localize the sensor position to find similar waveform from waveform database. This paper proposes a place recognitionmethod based on waveform matching, presents a number of experiments that illustrate the high positon estimation accuracy of our UWB radar-based localization system, and shows the resulting loop detection performance in a typical indoor office environment and a forest.

The effectiveness of education or behavioral interventions on adherence to phosphate control in adults receiving hemodialysis: A systematic review protocol

The objective of this review is to identify the effectiveness of education or behavioral interventions on adherence to phosphate control in adults with end stage kidney disease (ESKD) receiving hemodialysis (HD).

A survey of patients' experience of pain and other symptoms while receiving care from palliative care services

Context In Australia, patients at the end of life with complex symptoms and needs are often referred to palliative care services (PCSs), but little is known about the symptoms of patients receiving palliative care in different settings. Objective To explore patients’ levels of pain and other symptoms while receiving care from PCSs. Method PCSs registered through Australia's national Palliative Care Outcomes Collaboration (PCOC) were invited to participate in a survey between 2008 and 2011. Patients (or if unable, a proxy) were invited to complete the Palliative Care Outcome Scale. Results Questionnaires were completed for 1800 patients. One-quarter of participants reported severe pain, 20% reported severe ‘other symptoms’, 20% reported severe patient anxiety, 45% reported severe family anxiety, 66% experienced depressed feelings and 19% reported severe problems with self-worth. Participants receiving care in major cities reported higher levels of depressed feelings than participants in inner regional areas. Participants receiving care in community and combined service settings reported higher levels of need for information, more concerns about wasted time, and lower levels of family anxiety and depressed feelings when compared to inpatients. Participants in community settings had lower levels of concern about practical matters than inpatients. Conclusions Patients receiving care from Australian PCSs have physical and psychosocial concerns that are often complex and rated as ‘severe’. Our findings highlight the importance of routine, comprehensive assessment of patients’ concerns and the need for Specialist Palliative Care clinicians to be vigilant in addressing pain and other symptoms in a timely, systematic and holistic manner, whatever the care setting.

How does symptom burden differ in people with advanced CKD who are non-dialysis or currently receiving dialysis?

Background Chronic kidney disease (CKD) leads to a range of symptoms which are often under-recognised. Little is known about the full range of symptoms, particularly in who are pre-dialysis. Understanding symptom prevalence, distress, severity and frequency will help prioritise symptom management. Aims To examine symptom burden in advanced CKD (stages 4 and 5) and compare the symptom experience between those receiving dialysis or those who are pre-dialysis. Methods Using a cross-sectional design, a convenience sample of 436 people from three hospitals completed the Modified Dialysis Symptom Index (MDSI). Demographic and renal history data was also collected. Based on the 32 symptoms, we compared the prevalence, severity, distress and frequency of each symptom by treatment modality. Results Mean age was 48 years (range 18-87 years) and 53% were male. 75.5% (haemodialysis = 287; peritoneal dialysis = 42) were receiving dialysis and 24.5% (n = 107) were pre-dialysis. Overall, the mean symptom prevalence was 12.6 ± 7.9 and the most prevalent symptoms were fatigue (77%), bone or joint pain (60.3%) and itching (59.6%) across all CKD groups. The distress, severity and frequency of the symptoms were higher in the dialysis group. However, a higher frequency of psychological symptoms (worrying, feeling nervous and depression) were reported in the pre-dialysis group. Implication for clinical practice Patients with advanced CKD have a high symptom burden with those who are pre-dialysis needing greater psychological support. The MDSI could be used in nursing practice to screen patients for symptoms which could lead to timely and appropriate interventions.

Learned ultra-wideband RADAR sensor model for augmented LIDAR-based traversability mapping in vegetated environments

In vegetated environments, reliable obstacle detection remains a challenge for state-of-the-art methods, which are usually based on geometrical representations of the environment built from LIDAR and/or visual data. In many cases, in practice field robots could safely traverse through vegetation, thereby avoiding costly detours. However, it is often mistakenly interpreted as an obstacle. Classifying vegetation is insufficient since there might be an obstacle hidden behind or within it. Some Ultra-wide band (UWB) radars can penetrate through vegetation to help distinguish actual obstacles from obstacle-free vegetation. However, these sensors provide noisy and low-accuracy data. Therefore, in this work we address the problem of reliable traversability estimation in vegetation by augmenting LIDAR-based traversability mapping with UWB radar data. A sensor model is learned from experimental data using a support vector machine to convert the radar data into occupancy probabilities. These are then fused with LIDAR-based traversability data. The resulting augmented traversability maps capture the fine resolution of LIDAR-based maps but clear safely traversable foliage from being interpreted as obstacle. We validate the approach experimentally using sensors mounted on two different mobile robots, navigating in two different environments.

Hampson type heat-exchanger technology and economic evaluation for LNG re- gasification and power generation At LNG receiving terminals

The system for high utilization of LNG cold energy is proposed by use of process simulator. The proposed design is a closed loop system, and composed by a Hampson type heat exchanger, turbines, pumps and advanced humid air turbine (AHAT) or Gas turbine combined cycle (GTCC). Its heat sources are Boil-off gas and cooling water for AHAT or GTCC. The higher cold exergy recovery to power can be about 38 to 56% as compared to the existing cold power generation of about 20% with a Rankine cycle of a single component. The advantage of the proposed system is to reduce the number of heat exchangers. Furthermore, the environmental impact is minimized because the proposed design is a closed loop system. A life cycle comparative cost is calculated to demonstrate feasibility of the proposed design. The development of the Hampson type exchangers is expected to meet the key functional requirements and will result in much higher LNG cold exergy recovery and the overall system performance i.e. re-gasification. Additionally, the proposed design is expected to provide flexibility to meet different gas pressure suited for the deregulation of energy system in Japan and higher reliability for an integrated boil-off gas system.

Serum immunoglobulin G directed against porcine trypsin in the serum of cystic fibrosis children receiving porcine pancreatic enzyme supplements

Cystic fibrosis (CF) patients require pancreatic enzyme replacement therapy to correct pancreatic insufficiency. These enzymes are derived from porcine pancreas and are known to be antigenic. To determine the possible clinical consequences, a specific ELISA was developed to detect IgG antibody directed against porcine trypsin (PTAb) in the sera of CF patients. The assay was used to evaluate the occurrence of PTAb in a cross sectional study of 103 CF patients in relation to the introduction of porcine enzyme therapy, clinical status and genotype. Antibodies against porcine trypsin were detected in the sera of 63% of patients unrelated to the age of commencement or the duration of enzyme therapy. No differences were observed in the clinical status of CF patients who had developed PTAb (n = 65) and those who had no detectable PTAb (n = 38) as determined from: the current prescribed dose of porcine pancreatic enzyme capsules; Z scores for height and weight; and respiratory function tests. It is suggested that the PTAb commonly found in the sera of CF patients are of doubtful clinical significance but the prospect of PTAb contributing to immune complex disease should be examined further.

Analysis of human immunodeficiency virus type 1 drug resistance in children receiving nucleoside analogue reverse-transcriptase inhibitors plus nevirapine, nelfinavir, or ritonavir (Pediatric AIDS Clinical Trials Group 377)

In Pediatric AIDS Clinical Trials Group 377, antiretroviral therapy-experienced children were randomized to 4 treatment arms that included different combinations of stavudine, lamivudine (3TC), nevirapine (Nvp), nelfinavir (Nfv), and ritonavir (Rtv). Previous treatment with zidovudine (Zdv), didanosine (ddI), or zalcitabine (ddC) was acceptable. Drug resistance ((R)) mutations were assessed before study treatment (baseline) and at virologic failure. Zdv(R), ddI(R), and ddC(R) mutations were detected frequently at baseline but were not associated with virologic failure. Children with drug resistance mutations at baseline had greater reductions in virus load over time than did children who did not. Nvp(R) and 3TC(R) mutations were detected frequently at virologic failure, and Nvp(R) mutations were more common among children receiving 3-drug versus 4-drug Nvp-containing regimens. Children who were maintained on their study regimen after virologic failure accumulated additional Nvp(R) and 3TC(R) mutations plus Rtv(R) and Nfv(R) mutations. However, Rtv(R) and Nfv(R) mutations were detected at unexpectedly low rates.

A precision apparatus, with solid phase micro-extraction monitoring capability, for incorporation studies of gaseous precursors into insect-derived metabolites

An apparatus is described that facilitates the determination of incorporation levels of isotope labelled, gaseous precursors into volatile insect-derived metabolites. Atmospheres of varying gas compositions can be generated by evacuation of a working chamber followed by admission of the required levels of component gases, using a precision, digitised pressure read-out system. Insects such as fruit-flies are located initially in a small introduction chamber, from which migration can occur downwards into the working chamber. The level of incorporation of labelled precursors is continuously assayed by the Solid Phase Micro Extraction (SPME) technique and GC-MS analyses. Experiments with both Bactrocera species (fruit-flies) and a parasitoid wasp, Megarhyssa nortoni nortoni (Cresson) and oxygen-18 labelled dioxygen illustrate the utility of this system. The isotope effects of oxygen-18 on the carbon-13 NMR spectra of 1,7- dioxaspiro[5,5]undecane are also described.

A simple vibrating reed apparatus for use at low temperatures

The authors report the design and construction of a very simple vibrating reed apparatus with automatic frequency locking capability where the resonance frequency and the internal friction can be recorded continuously as a function of temperature. The apparatus is particularly suitable for studies down to liquid helium temperatures or below.

Comparative productivity of irrigated short-term ryegrass (Lolium multiflorum) pasture receiving nitrogen, grown alone or in a mixture with white (Trifolium repens) and Persian (T. resupinatum) clovers

Dairy farms in subtropical Australia use irrigated, annually sown short-term ryegrass (Lolium multiflorum) or mixtures of short-term ryegrass and white (Trifolium repens) and Persian (shaftal) (T. resupinatum) clover during the winter-spring period in all-year-round milk production systems. A series of small plot cutting experiments was conducted in 3 dairying regions (tropical upland, north Queensland, and subtropical southeast Queensland and northern New South Wales) to determine the most effective rate and frequency of application of nitrogen (N) fertiliser. The experiments were not grazed, nor was harvested material returned to the plots, after sampling. Rates up to 100 kg N/ha.month (as urea or calcium ammonium nitrate) and up to 200 kg N/ha every 2 months (as urea) were applied to pure stands of ryegrass in 1991. In 1993 and 1994, urea, at rates up to 150 kg N/ha.month and to 200 kg N/ha every 2 months, was applied to pure stands of ryegrass; urea, at rates up to 50 kg N/ha.month, was also applied to ryegrass-clover mixtures. The results indicate that applications of 50-85 kg N/ha.month can be recommended for short-term ryegrass pastures throughout the subtropics and tropical uplands of eastern Australia, irrespective of soil type. At this rate, dry matter yields will reach about 90% of their potential, forage nitrogen concentration will be increased, there is minimal risk to stock from nitrate poisoning and there will be no substantial increase in soil N. The rate of N for ryegrass-clover pastures is slightly higher than for pure ryegrass but, at these rates, the clover component will be suppressed. However, increased ryegrass yields and higher forage nitrogen concentrations will compensate for the reduced clover component. At application rates up to 100 kg N/ha.month, build-up of NO3--N and NH4+-N in soil was generally restricted to the surface layers (0-20 cm) of the soil, but there was a substantial increase throughout the soil profile at 150 kg N/ha.month. The build-up of NO3--N and NH4+-N was greater and was found at lower rates on the lighter soil compared with heavy clays. Generally, most of the soil N was in the NO3--N form and most was in the top 20 cm.