Moderating mycorrhizas: arbuscular mycorrhizas modify rhizosphere chemistry and maintain plant phosphorus status within narrow boundaries

Pastures often experience a pulse of phosphorus (P) when fertilized. We examined the role of arbuscular mycorrhizal fungi (AMF) in the uptake of P from a pulse. Five legumes (Kennedia prostrata, Cullen australasicum, Bituminaria bituminosa, Medicago sativa and Trifolium subterraneum) were grown in a moderate P, sterilized field soil, either with (+AMF) or without (−AMF) addition of unsterilized field soil. After 9–10 weeks, half the pots received 15 mg P kg−1 of soil. One week later, we measured: shoot and root dry weights; percentage of root length colonized by AMF; plant P, nitrogen and manganese (Mn) concentrations; and rhizosphere carboxylates, pH and plant-available P. The P pulse raised root P concentration by a similar amount in uncolonized and colonized plants, but shoot P concentration increased by 143% in uncolonized plants and 53% in colonized plants. Inoculation with AMF decreased the amount of rhizosphere carboxylates by 52%, raised rhizosphere pH by ∼0.2–0.7 pH units and lowered shoot Mn concentration by 38%. We conclude that AMF are not simply a means for plants to enhance P uptake when P is limiting, but also act to maintain shoot P within narrow boundaries and can affect nutrient uptake through their influence on rhizosphere chemistry.

Putting the P in Ptilotus: a phosphorus accumulating herb native to Australia

Background and Aims Ptilotus polystachyus (green mulla mulla; ptilotus) is a short-lived perennial herb that occurs widely in Australia in arid and semi-arid regions with nutrient poor soils. As this species shows potential for domestication, its response to addition of phosphorus (P) and nitrogen (N) was compared to a variety of the domesticated exotic perennial pasture herb Cichorium intybus (chicory), ‘Puna’. Methods Pots were filled with 3 kg of an extremely nutrient-deficient sterilized field soil that contained 3 mg kg−1 mineral N and 2 mg kg−1 bicarbonate-extractable P. The growth and P and N accumulation of ptilotus and chicory in response to seven rates of readily available phosphorus (0–300 mg P pot−1) and nitrogen (N) (0–270 mg N pot−1) was examined. Key Results Ptilotus grew extremely well under low P conditions: shoot dry weights were 23, 6 and 1·7 times greater than for chicory at the three lowest levels of P addition, 0, 15 and 30 mg P pot−1, respectively. Ptilotus could not downregulate P uptake. Concentrations of P in shoots approached 4 % of dry weight and cryo-scanning electron microscopy and X-ray microanalysis showed 35–196 mm of P in cell vacuoles in a range of tissues from young leaves. Ptilotus had a remarkable tolerance of high P concentrations in shoots. While chicory exhibited symptoms of P toxicity at the highest rate of P addition (300 mg P pot−1), no symptoms were present for ptilotus. The two species responded in a similar manner to addition of N. Conclusions In comparison to chicory, ptilotus demonstrated an impressive ability to grow well under conditions of low and high P availability. Further study of the mechanisms of P uptake and tolerance in ptilotus is warranted.

Histomorphologic evaluation of Ti-13Nb-13Zr alloys processed via powder metallurgy. A study in rabbits

This study presents the in-vivo evaluation of Ti-13Nb-13Zr alloy implants obtained by the hydride route via powder metallurgy. The cylindrical implants were processed at different sintering and holding times. The implants` were characterized for density, microstructure (SEM), crystalline phases (XRD), and bulk (EDS) and surface composition (XPS). The implants were then sterilized and surgically placed in the central region of the rabbit`s tibiae. Two double fluorescent markers were applied at 2 and 3 weeks, and 6 and 7 weeks after implantation. After an 8-week healing period, the implants were retrieved, non-decalcified section processed, and evaluated by electron, UV light (fluorescent labeling), and light microscopy (toluidine blue). BSE-SEM showed close contact between bone and implants. Fluorescent labeling assessment showed high bone activity levels at regions close to the implant surface. Toluidine blue staining revealed regions comprising osteoblasts at regions of newly forming/formed bone close to the implant surface. The results obtained in this study support biocompatible and osseoconductive properties of Ti-13Nb-13Zr processed through the hydride powder route. (c) 2007 Published by Elsevier B.V.

Single-use Trocar Is it Possible to Reprocess it After the First Use?

The aim of this study was to verify and describe the presence of microorganisms in the single-use trocar after its use in surgical procedures, and after this device was submitted to cleaning, conditioning, and sterilization by physicochemical processes (formaldehyde, ethylene oxide, and hydrogen peroxide plasma). Twenty-eight trocars of the Ethicon, Auto-suture, and Aesculap brands, were randomly selected and analyzed after laparoscopic cholecystectomy. The results have shown that cultures grown of the material collected from the trocars, immediately after its use and before its sterilization process, showed the presence of bacteria and fungi in 46.5% (13). In 53.5% (15) of the trocars, the presence of microorganisms was not detected, very likely due to niche`s scarcity. In the cultures grown of the 28 trocars after being submitted to sterilization processes, the presence of microorganisms was not verified. We can therefore conclude that although trocars possess compartments not easily accessed for cleaning, these devices can be adequately cleaned and effectively sterilized, when well manipulated, in the institution where the study was carried out by the processes of steam sterilization at low temperature and formaldehyde, ethylene oxide, and hydrogen peroxide plasma.

Comparison of Two Rotary Systems in Root Canal Preparation Regarding Disinfection

Introduction: The aim of the present study was to determine the disinfection of preparations carried out by using the Protaper or MTwo system in canals infected with Enterococcus faecalis. Methods: Twenty-eight distobuccal canals of upper molars were used, in which the canals were sterilized after being enlarged to #20 file and then contaminated with an inoculation of a culture of E. faecalis. After the incubation period, bacterial samples were collected and were seeded on plates for analysis of colony-forming units (CFU)/mL. The teeth were divided into 2 groups according to the rotary system used for instrumentation; 2 noninstrumented teeth served as the control group. Then bacterial samples were collected and were seeded on plates for analysis of CFU/mL again. The data obtained were evaluated by the Wilcoxon and Mann-Whitney U tests. Results: Bacterial reduction was 81.94% and 84.29%, respectively, in Pro Taper and Mtwo systems, and there was no statistically significant difference (P > .05). Conclusions: Both systems, Pro Taper and Mtwo, reduced the amount of bacteria in the mechanical disinfection of the root canal system, demonstrating that they are suitable for this purpose. (J Endod 2010;36:1238-1240)

Inactivation kinetics of polyphenol oxidase and peroxidase in green coconut water by microwave processing

The inactivation kinetics of enzymes polyphenol oxidase (PPO) and peroxidase (POD) was studied for the batch (discontinuous) microwave treatment of green coconut water. Inactivation of commercial PPO and POD added to sterile coconut water was also investigated. The complete time-temperature profiles of the experimental runs were used for determination of the kinetic parameters D-value and z-value: PPO (D(92.20 degrees C) = 52 s and z = 17.6 degrees C); POD (D(92.92 degrees C) = 16 s and z = 11.5 degrees C); PPO/sterile coconut water: (D(84.45 degrees C) = 43 s and z = 39.5 degrees C) and POD/sterile coconut water: (D(86.54 degrees C) = 20 s and z = 19.3 degrees C). All data were well fitted by a first order kinetic model. The enzymes naturally present in coconut water showed a higher resistance when compared to those added to the sterilized medium or other simulated solutions reported in the literature. The thermal inactivation of PPO and POD during microwave processing of green coconut water was significantly faster in comparison with conventional processes reported in the literature. (C) 2008 Elsevier Ltd. All rights reserved.

Synergism Between Keratinocyte Growth Factor and Carboxymethyl Chitosan Reduces Pericardial Adhesions

Background. Mesothelial injury is the pivot in the development of adhesions. An increase in the proliferation of mesothelial cells was verified by in vitro studies with the use of keratinocyte growth factor (KGF). This study investigated the influence of KGF associated with thermo-sterilized carboxymethyl chitosan (NOCCts) in the reduction of pericardial adhesions. Methods. An induction model of pericardial adhesion was carried out in 24 pigs. Animals were randomly allocated to receive topical application of KGF, KGF + NOCCts, NOCCts, or saline (control). At 8 weeks, intra-pericardial adhesions were evaluated and a severity score was established. The time spent to dissect the adhesions and the amount of sharp dissection used, were recorded. Histologic sections were stained with sirius red for a morphometric evaluation using a computer-assisted image analysis system. Cytokeratin AE1/AE3 immunostaining were employed to identify mesothelial cells. Results. The severity score expressed in median (minimum to maximum), in relation to the control group (17 [15 to 18]), was lower in the KGF + NOCCts group (7 [6 to 9], p < 0.01) followed by the KGF group (11.5 [9 to 12], 0.01 < p < 0.05) and the NOCCts group (12 [9 to 14], p > 0.05). The dissection time was significantly lower in the KGF + NOCCts group (7.1 +/- 0.6 vs 33.9 +/- 9.2 minutes, p < 0.001). A significantly less sharp dissection was also required in the KGF + NOCCts group. In the adhesion segment, a decreased collagen proportion was found in the KGF + NOCCts group (p < 0.05). Mesothelial cells were present more extensively in groups in which KGF was delivered (p = 0.01). Conclusions. The use of KGF associated with NOCCts resulted in a synergic action that decreases postoperative pericardial adhesions in a highly significant way. (Ann Thorac Surg 2010; 90: 566-72) (C) 2010 by The Society of Thoracic Surgeons

Solar energy in asia, in Kobe, Japan, september 1989 : Reports from ISES solar world congress and from study visits in India and Pakistan

The ISES Solar World Congress Clean and Safe Energy Forever was held in Kobe, Japan, September 4-8, 1989. Short impressions from the conference and the simultaneous exhibition are given. On our (separate) ways to Kobe, Eriksson visited institutions in the Bombay, India area, and Broman one institution in Islamabad, Pakistan. Accounts of these visits are given. Three papers presented in Kobe are included in an Appendix.

Att prata ihop sig i rätten

Negotiating experience in the court How do judges assess witness credibility, and how do they proceed to reach sustainable conclusions in a criminal court? This article is based on discussions in four focus groups with lay judges in Swedish district courts. In criminal court trials, a version of an event is generally reinforced if it is confirmed by witnesses. However, if their narratives are too similar, none of them is found trustworthy. The focus group participants agreed that if witnesses were suspected of having discussed their individual experiences of an event and accommodated them into a common story, their testimonies were not considered credible. While testimonies should ideally be untainted by other people’s impressions and opinions, other rules govern the truth of the court. The lay judges appreciated their deliberations, including negotiations on impressions and memories of the trial, and they sometimes adjusted their perceptions in the light of information provided by other members of the court. However, if the lay judges are viewed as witnesses of what takes place in the trial, this gives rise to a paradox: While witness negotiations on experiences are regarded as a means to construct a false or biased story, the same kind of interaction between the judges is considered necessary to establish a consensual truth of what actually happened.

Students' perspective of online learning

When a student commences a course of study that includes an online component the initial feedback academics receive can reflect their fear of the online concept, their bias against the use of technology, as well as difficulties they may have encountered with using the supporting technologies rather than with online learning per se. In second semester 2002, an evaluation of an online unit in the B. Computing was conducted at the end of the semester to gain a better understanding of students’ perceptions of online learning as well as the effectiveness of the technologies that support these activities. We report some preliminary results from the evaluation. Initial indications are that poor first impressions are reflected in students’ perceptions of the overall online learning experience. We highlight some areas, normally considered outside the immediate domain of eLearning, that must be attended to in order to minimise the potential negative impact on students, maximise the benefits of learning online and improve the learning experience for students.

Degradation of phenanthrene and pyrene in soil slurry reactors with immobilized bacteria Zoogloea sp.

The environmental fate of polycyclic aromatic hydrocarbons (PAHs) in soils is motivated by their wide distribution, high persistence, and potentially deleterious effect on human health. Polycyclic aromatic hydrocarbons constitute the largest group of environmental contaminants released in the environment. Therefore, the potential biodegradation of these compounds is of vital importance. A biocarrier suitable for the colonization by micro-organisms for the purpose of purifying soil contaminated by polycyclic aromatic hydrocarbons was developed. The optimized composition of the biocarrier was polyvinyl alcohol (PVA) 10%, sodium alginate (SA) 0.5%, and powdered activated carbon (PAC) 5%. There was no observable cytotoxicity of biocarriers on immobilized cells and a viable cell population of 1.86 × 10¹⁰ g^–1 was maintained for immobilized bacterium. Biocarriers made from chemical methods had a higher biodegradation but lower mechanical strengths. Immobilized bacterium Zoogloea sp. had an ideal capability of biodegradation for phenanthrene and pyrene over a relative wide concentration range. The study results showed that the biodegradation of phenanthrene and pyrene reached 87.0 and 75.4%, respectively, by using the optimal immobilized method of Zoogloea sp. cultivated in a sterilized soil. Immobilized Zoogloea sp. was found to be effective for biodegrading the soil contaminated with phenanthrene and pyrene. Even in "natural" (unsterilized) soil, the biodegradation of phenanthrene and pyrene using immobilized Zoogloea sp. reached 85.0 and 67.1%, respectively, after 168 h of cultivation, more than twice that achieved if the cells were not immobilized on the biocarrier. Therefore, the immobilization technology enhanced the competitive ability of introduced micro-organisms and represents an effective method for the biotreatment of soil contaminated with phenanthrene and pyrene.

Lawsone : a novel reagent for the detection of latent fingermarks on paper surfaces

Lawsone (2-hydroxy-1,4-naphthoquinone) reacts with latent fingermark deposits on paper surfaces to yield purple-brown impressions of ridge details which are also photoluminescent; this compound represents the first in a completely new class of fingermark detection reagents.

Extracting fingerprint features using textures

Personal identification of individuals is becoming increasingly adopted in society today. Due to the large number of electronic systems that require human identification, faster and more secure identification systems are pursued. Biometrics is based upon the physical characteristics of individuals; of these the fingerprint is the most common as used within law enforcement. Fingerprint-based systems have been introduced into the society but have not been well received due to relatively high rejection rates and false acceptance rates. This limited acceptance of fingerprint identification systems requires new techniques to be investigated to improve this identification method and the acceptance of the technology within society. Electronic fingerprint identification provides a method of identifying an individual within seconds quickly and easily. The fingerprint must be captured instantly to allow the system to identify the individual without any technical user interaction to simplify system operation. The performance of the entire system relies heavily on the quality of the original fingerprint image that is captured digitally. A single fingerprint scan for verification makes it easier for users accessing the system as it replaces the need to remember passwords or authorisation codes. The identification system comprises of several components to perform this function, which includes a fingerprint sensor, processor, feature extraction and verification algorithms. A compact texture feature extraction method will be implemented within an embedded microprocessor-based system for security, performance and cost effective production over currently available commercial fingerprint identification systems. To perform these functions various software packages are available for developing programs for windows-based operating systems but must not constrain to a graphical user interface alone. MATLAB was the software package chosen for this thesis due to its strong mathematical library, data analysis and image analysis libraries and capability. MATLAB enables the complete fingerprint identification system to be developed and implemented within a PC environment and also to be exported at a later date directly to an embedded processing environment. The nucleus of the fingerprint identification system is the feature extraction approach presented in this thesis that uses global texture information unlike traditional local information in minutiae-based identification methods. Commercial solid-state sensors such as the type selected for use in this thesis have a limited contact area with the fingertip and therefore only sample a limited portion of the fingerprint. This limits the number of minutiae that can be extracted from the fingerprint and as such limits the number of common singular points between two impressions of the same fingerprint. The application of texture feature extraction will be tested using variety of fingerprint images to determine the most appropriate format for use within the embedded system. This thesis has focused on designing a fingerprint-based identification system that is highly expandable using the MATLAB environment. The main components that are defined within this thesis are the hardware design, image capture, image processing and feature extraction methods. Selection of the final system components for this electronic fingerprint identification system was determined by using specific criteria to yield the highest performance from an embedded processing environment. These platforms are very cost effective and will allow fingerprint-based identification technology to be implemented in more commercial products that can benefit from the security and simplicity of a fingerprint identification system.

Phenomenon of ordinariness in nursing

This phenomenological research aimed to illuminate the nature and effects of ordinariness in nursing and to discover whether the phenomenon enhanced the nursing encounter. The researcher worked as a participant observer with six registered nurses in a Professorial Nursing Unit. Following each interaction, the researcher wrote her impressions in a personal-professional journal and audiotaped conversations with the respective nurses and patients to gain their impressions. Using a theoretical framework of the phenomenological concepts of lived experience, Dasein, Being-in-the-world and fusion of horizons as an underpinning methodology, an initial hermeneutical analysis and interpretation of the impressions generated qualities and activities indicative of the aspects of the phenomenon of ordinariness in nursing. The second phase of the analysis and interpretation sought to illuminate the nature of the phenomenon itself. Eight actualities of the nature of the phenomenon emerged: 'allowingness,' 'straightforwardness,' 'self-likeness,' 'homeliness,' 'favourableness,' 'intuneness,' 'lightheartedness' and 'connectedness.' These actualities were described in relation to the phenomenon of interest. The effects of the phenomenon were the creative potential to enhance the nursing encounter and included many and various effects of facilitation, fair play, familiarity, family, favouring, feelings, fun and friendship. The research found that nurses and patients shared a common sense of humanity, which enhanced the nursing encounter. Within the context of caring, the nurses were ordinary people, perceived as being extraordinarily effective, by the very ways in which their humanness shone through their knowledge and skills, to make their whole being with patients something more than just professional helping. The shared sense of ordinariness between nurses and patients made them as one in then- humanness and created a special place, in which the relative strangeness of the experience of being in a health care setting, could be made familiar and manageable.

Importance of the contribution of Australians to the penetration of China by the China Inland Mission in the period 1888-1953, with particular reference to the work of Australian women missionaries

Australians, in the main, are unaware of the role which Australia played in the evangelization of China in the late nineteenth and the first half of the twentieth century. Most would never have heard of the China Inland Mission (CIM), the largest of the Protestant bodies which penetrated the Middle Kingdom, and few would know of the contribution that its Australian contingent, which consistently comprised about a tenth of the CIM's numbers, made towards the Christianization of that vast country. This thesis aims to raise the level of awareness in this area. Academic researchers have not totally neglected to examine the proselytization of China, and historians of the stature of Latourette have not let it escape their attention. However, most of the studies which have not merely fleetingly focused on the subject while viewing a larger canvas, have been North American, singling out the efforts of United States and Canadian bodies in introducing Christianity to the Chinese. Here, authors like Amerding, Bacon, Creighton, Gates, Hawkes, Ho, Ko, Mensendiek, Michell and Quale have left their mark. In the case of the present thesis, the outlook from which events played out in China are viewed is firmly based in Australia rather than North America. Earlier Australian research has been scarce, and is dominated by Loane and Dixon. Loane, evidently primarily working from Australasian Council minutes, mainly concentrates on the efforts of the CIM's Home Council, examining its endeavours decade by decade against a backdrop of contemporaneous events in China, and briefly referring to aspects of the lives of a cross-section of Australasian missionaries, without providing much idea about what they actually did in the field or what they achieved there. Because of its preoccupation with the Home Council, which never admitted women into its ranks, Loane's treatise is systemically biased towards men, though the more prominent of the women, like Mary Reed and Susie Garland, are given due recognition. The current thesis looks in detail at what Australians did in the field, the level of success they achieved, and at the particular contribution of Australian women towards the evangelization of China. Dixon took upon herself the formidable task of examining the endeavours of all missions in China which contained Australian missionaries. Because of the magnitude of her task, she could not focus to any great extent on particular missions, nor pursue in any detail the work of individual Australian missionaries. Like Loane, she was unable to explore what they actually did in the field or what they achieved there. Neither could she delve to any depth into the work of Australian women missionaries, though on the basis of the information she had accumulated, she drew the conclusion that Australian women had largely only brought about some unintended feminist consequences amongst Chinese women. This sweeping generalization failed to take into account the other very real social changes for Chinese women the Australian female missionaries quite purposely helped to bring about, and this thesis makes good that omission. This thesis studies aspects of the Australian missionary endeavour which both Loane and Dixon have neglected, thereby breaking new ground, and sets out to correct erroneous impressions which Dixon's dissertation has left on the historical record. One of these impressions concerned the longevity of the effect of the Australian effort in China. She had the View, writing in 1978, that the Chinese Church was moribund (a view shared by Varg and Lacy) , and that therefore the effects attributable to the endeavours of any nationality had proved fruitless, whereas the author is able to show, using modern-day sources, that the church has burgeoned in recent years thanks to earlier missionary endeavours and later neo-evangelistic efforts like Gospel radio, and now has a complement of perhaps 50 million adherents, making it second only to the United States in the size of its Protestant evangelical population. Another impression she left was that the Australian input into the evangelization of China can be largely dismissed because no totally Australian organization emerged, leaving the direction of Australia's effort in other hands. Contrary to that impression, the author shows that the Australian impact in China was significant and that Australians enjoyed more power than Dixon ever imagined. The author also shows that Australians were accepted as the equal of other nationalities in the CIM once they had acquired the necessary field expertise, a factor which doubtless also applied in respect of other missions with Australian components in China. Marchant has suggested that it is a fiction perpetuated by mission periodicals that Christianity spread and progressed in a determined manner in China. This thesis establishes that within the CIM's bailiwick, though there was some patchiness, Christianity progressed steadily and inexorably. One mission alone, the CIM, is concentrated upon, firstly in order to render the data manageable, secondly because it was the largest mission in China and had a sizeable Australian (including female) contingent, and thirdly because it exemplified many of the problems which would have been faced by missions in that country and their Australian components. The methodology employed is multifaceted. The written testimony of the missionaries themselves, contained in CIM periodicals, Field Bulletins, Monthly Notes, Annual Reports, autobiographies, personal files, diaries and letters is used to illustrate various aspects of the CIM's work in which Australians were engaged. This approach is augmented by other sources such as China and Australasian Home Council Minutes, missionary conference reports, Candidates' Books, biographies, and other selected material from archival holdings in Australia, Singapore, the United Kingdom, America and Canada. Statistics, especially ratio analyses and growth rate comparisons are used to demonstrate the relative success of different missions, missionaries and genders. Also employed are reminiscences of missionaries and descendants obtained by personal interview, and these are aggregated to provide some general conclusions. Data from these various sources have been synthesized to serve the central objective of demonstrating the importance of the contribution of Australians to the penetration of China by the CIM in the period 1888-1953 with particular reference to the work of Australian women missionaries.