Control and prevention of microbially influenced corrosion using cephalopod chitosan and its derivatives: A review

Microbially influenced corrosion (MIC) of metals is an important industrial problem, causing 300-500 billion dollars of economic loss worldwide each year. It is very challenging to prevent or control the MIC in the marine environment. Eco-friendly coatings embedded with corrosion inhibitors developed from natural products may be a successful approach for MIC prevention or control. As a natural renewable resource, cephalopod chitosan has a number of unique biological properties, such as antibacterial, antifungal and non-toxicity effects, which attract scientific and industrial interests for potential applications. Chitosan is a positively charged molecule, and the negatively charged bacterial cell wall is the target of its antimicrobial action. Chitosan binds to the bacterial cell wall and disrupts the normal functions of the membrane by, for example, facilitating the leakage of intracellular components and impeding the transport of nutrients into the cells. Interestingly, chitosan is an excellent film-forming polymer. Chitosan may be applied as an antimicrobial coating substance for the prevention or control of MIC. Furthermore, the antimicrobial chitosan coating can serve as a basal matrix, in which other antimicrobial or anticorrosive substances like chitosan nanoparticles, chitosan silver nanoparticles, quorum sensing inhibitors (QSI) or the combination of these compounds, can be embedded to achieve synergistic anticorrosive effects. A combination of field and laboratory experiments will be conducted to test this hypothesis for preventing or controlling MIC in the marine environment. Thus, the proposed review will identify new eco-friendly MIC inhibitors and will assay their potential in future applications in the anti-corrosion industry.

Sulfation of chitosan from Sepia kobiensis as potential anticoagulant and antibacterial molecule

The present work aimed to synthesis of chitin, chitosan and sulfation of chitosan from cuttlebone of cuttlefish Sepia kobiensis. Principally chitin was extracted through sequential processes of demineralisation and deproteinzation. Then chitosan was synthesized by a deacetylation and finally sulfated at semi-heterogeneous condition using chlorosulfonic acid in N,N-dimethylformamide. The synthesized macromolecules were characterized for its structural, physical and thermal (CHN, DDA, FT-IR, NMR, XRD, Viscometric analysis, SEM and DSC) properties. Apart from anticoagulant potential of the sulfated chitosan was tested using human plasma by means of activated partial thromboplastin time (APTT) and prothrombin time (PT). Further sulfated chitosan was tested for antibacterial potential by well diffusion method against eleven human pathogenic clinical isolates of both Gram positive and Gram-negative strains and minimum inhibitory concentrations (MIC) was calculated accordingly. The results of this study revealed the effectiveness of the sulfated chitosan at semi-heterogeneous conditions as a potent antibacterial and anticoagulant molecule.

Anti-ovarian cancer potential of phytocompound and extract from South African medicinal plants and their role in the development of chemotherapeutic agents

Ovarian cancer (OC) accounts for the highest tumor-related mortality among the gynecologic malignancies. Most of the OC patients diagnosed with advanced-stage (III and IV) this situation creates panic and provokes an emergency to discover a new therapeutic strategy. Plants that possess medicinal properties are gaining attention as they are enriched with various chemical compounds that are potential to treat various diseases. It is a prolonged process to provide innovative and significant leads against a range of pharmacological targets for a human disease management system. Though challenges and difficulties are faced in the development of a new drug, the emergence of combinatorial chemistry is providing a new ray of hope and also, the executed effort in discovering the drug, and a chemical compound has been remarkably successful. This review discussed the role of medicinal plants that are native of South Africa in treating the Ovarian Cancer and in drug discovery.

The value of local registry data for describing cervical cancer management and outcomes over three decades in Australia

Registry data on invasive cervical cancers (n = 1,274) from four major hospitals (1984-2012) were analysed to determine their value for informing local service delivery in Australia. The methodology comprised disease-specific survival analyses using Kaplan-Meier product-limit estimates and Cox proportional hazards models and treatment analyses using logistic regression. Five- and 10-year survivals were 72% and 68%, respectively, equating with relative survival estimates for Australia and the USA. Most common treatments were surgery and radiotherapy. Systemic therapies increased in recent years, generally with radiotherapy, but were less common for residents from less accessible areas. Surgery was more common for younger women and early-stage disease, and radiotherapy for older women and regional and more advanced disease. The proportion of glandular cancers increased in-step with national trends. Little evidence of variation in risk-adjusted survival presented over time or by Local Health District. The study illustrates the value of local registry data for describing local treatment and outcomes. They show the lower use of systemic therapies among residents of less accessible areas which warrants further investigation. Risk-adjusted treatment and outcomes did not vary by socio-economic status, suggesting equity in service delivery. These data are important for local evaluation and were not available from other sources.

Occlusion of Posterior Fossa Dural Sinuses in Vein of Galen Malformation

BACKGROUND AND PURPOSE

Spontaneous or progressive occlusion of the posterior fossa dural sinuses is often observed in patients with vein of Galen malformation, which can affect the clinical course. The aim of this study was to examine the patency of the posterior fossa dural sinuses in patients with vein of Galen malformation and to analyze the clinical and angiographic course of this condition.

MATERIALS AND METHODS

We retrospectively reviewed 61 consecutive children with vein of Galen malformations. Clinical presentation, management, outcome, and angiographic change were analyzed for the patients with attention paid to all dural sinus occlusions.

RESULTS

Twenty patients (32.8%) demonstrated spontaneous sinus occlusion, mostly in the sigmoid sinus. This condition was not observed in neonates and was first discovered during infancy or childhood. Progression of sinus occlusion was seen in 10 patients, and the conditions of 6 of them deteriorated in accordance with the progression of sinus occlusion. After total or subtotal obliteration of the malformation by transarterial glue embolization, 13 patients recovered to healthy, 3 patients had only mild developmental delay, and 4 patients remained neurologically disabled.

CONCLUSIONS

Spontaneous sinus occlusion is not a rare condition and can result in neurologic deterioration in the natural history of untreated vein of Galen malformation. If signs of progressive sinus occlusion are noticed, early arteriovenous shunt reduction or elimination by transarterial glue embolization is expected to prevent permanent brain damage.

Abstract TP387: An Interdisciplinary Approach to Improving Acute Treatment- Implementation of the Rapid Acute Stroke Protocol

Background: Recent emergence of evidence for the effectiveness of intra-arterial treatment (IAT) of acute ischemic stroke secondary to large vessel occlusion (LVO) has prompted hospitals to examine the efficiency of their initial evaluation process. Mount Sinai Hospital has taken an interdisciplinary approach to hyper acute stroke care. It streamlined its process focusing on rapid triage of stroke, stroke team assessment, IV tPA administration and detection of LVO.

Rapid Acute Stroke Protocol (RASP), including early stroke team activation by the triage nurse was implemented in December 2014. Triage nurses were trained in the identification of stroke and stroke team activation. Feedback was provided to nursing leadership and individual participants on every treated case. A ‘team member of the month’ was established to promote ongoing enthusiasm and team rapport.

We hypothesized that the combination of new evidence and the introduction of RASP would increase the number of patients treated, decrease time to stroke team assessment and door to puncture (DTP) time.

Method: In this retrospective review of 51 consecutive patients with AIS treated with IAT from January 2014 until July 2015, the population was divided into two cohorts. Cohort 1 included patients treated from January 2014 through November 2014, prior to RASP initiation. Cohort 2 included patients treated from December 2014 through July 2015. Outcomes included number of patients treated, arrival to stroke team assessment, and DTP time.

Results: In cohort 1, .9 cases per month were treated with IAT compared to 5.1 per month in cohort 2, a 5.2 fold increase. A greater percentage of these patients arrived in the ED via inter-hospital transfer 56% vs 30%. There was a decrease in arrival time to stroke team assessment for cohort 2 vs cohort 1 (3 vs 9 minutes) and a reduction of 46.6% from DTP time (79 minutes vs 148 minutes p=<.001).

Conclusion: These findings demonstrate how an interdisciplinary approach to hyper acute care can have a dramatic effect on the stroke patient. Improved prenotification by EMS or the originating hospital contributed to immediate stroke team availability. However, key to RASP was empowering the triage nurse with the responsibility of stroke recognition and activation of the stroke code.

2-Ferrocenyl-3-nitro-2H-chromene

In the title compound, [Fe(C₅H₅)(C₁₄H₁₀NO₃)], the cyclo­penta­dienyl rings are in an eclipsed conformation and the pyran ring adopts a half-chair conformation. The mean plane of the pyran ring makes dihedral angles of 79.33 (1) and 80.73 (1)°, respectively, with the substituted and unsubstituted cyclo­penta­dienyl rings. In the crystal, pairs of C—H⋯O hydrogen bonds link the mol­ecules into inversion dimers with R₂²(16) motifs.

rac-3-(4-Chlorophenyl)-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-carbonitrile

The title compound, C₁₇H₁₁ClN₂O₂, which contains two stereogenic C atoms, crystallizes in a centrosymmetric space group as a racemate. The pyran ring and the isoxazole ring adopt sofa and twisted conformations, respectively. The dihedral angle between the benzene ring and the mean plane through the near coplanar atoms of the pyran ring is 4.17 (5)°. The mol­ecular conformation features a weak C—H⋯O contact. In the crystal, C—H⋯O hydrogen bonds link the mol­ecules, forming chains along the a-axis direction.

rac-Methyl 3-(2-meth-oxy-phen-yl)-3a,4-di-hydro-3H-chromeno[4,3-c]isoxazole-3a-carboxyl-ate

The title compound, C19H17NO5, comprising two stereogenic C atoms of the same configuration, crystallizes in a centrosymmetric space group as a racemate. The pyran ring adopts a half-chair conformation, while the isoxazole ring adopts an envelope conformation with the C atom bonded to the meth-oxy-phenyl group as the flap. The dihedral angle between the mean plane of the pyran ring and the adjacent benzene ring is 5.86 (5)°. In the crystal, mol-ecules are linked by a weak C-H⋯O hydrogen bond, forming a chain along the a axis.

(E)-1-Ferrocenyl-3-[2-(2-hy-droxy-eth-oxy)phen-yl]prop-2-en-1-one

In the title compound, [Fe(C5H5)(C16H15O3)], the cyclo-penta-dienyl rings are in an eclipsed conformation and the benzene ring makes dihedral angles of 10.84 (9) and 12.35 (9)°, respectively, with the substituted and unsubstituted cyclo-penta-dienyl rings. In the crystal, mol-ecules form inversion dimers through pairs of O-H⋯O hydrogen bonds. Weak C-H⋯O hydrogen bonds are observed between the dimers.

1-(4-{2-[(E)-3-(4-Chlorophenyl)-3-oxoprop-1-en-1-yl]phenoxy}butyl)-1H-indole-3-carbaldehyde

In the title compound, C28H24ClNO3, the dihedral angles between the central benzene ring and the indole ring system and the chlorobenzene ring are 70.81 (5) and 78.62 (5)°, respectively. The molecular structure is stabilized by a weak intramolecular C—H...O interaction. In the crystal, pairs of C—H...O hydrogen bonds link the molecules into inversion dimers with anR22(14) motif.

rac-Methyl 3-(2-meth-oxy-phen-yl)-1-phenyl-3,3a,4,9b-tetra-hydro-1H-chromeno[4,3-c]isoxazole-3a-carboxyl-ate

The title compound, C₂₅H₂₃NO₅, comprising two stereogenic carbon atoms of the same configuration, crystallizes in a centrosymmetric space group as a racemate. The six-membered pyran ring and the five-membered isoxazole ring adopt sofa and twisted conformations, respectively. The dihedral angle between the benzene ring and the mean plane through the near coplanar atoms of the pyran ring is 10.73 (7)°. The crystal structure features C—H⋯O hydrogen bonds.

rac-6-Ethoxy-3,3a,4,9b-tetrahydro-1,3-diphenyl-1H-chromeno[4,3-c]isoxazole-3a-carbonitrile

The title compound, C₂₅H₂₂N₂O₃, with three stereogenic centres, crystallizes in a centrosymmetric space group as a racemate. The pyran ring adopts a sofa conformation and the five-membered isoxazole ring exhibits an envelope conformation. The dihedral angle between the benzene ring and the mean plane through the near coplanar atoms of the pyran ring is 10.54 (9)°. In the crystal, no significant intermolecular interactions are observed.

(E)-3-Phenyl-2-(1-tosyl-1H-indol-3-ylcarbonyl)acrylonitrile

In the title compound, C₂₅H₁₈N₂O₃S, the indole moiety is planar and makes a dihedral angle of 89.95 (09)° with the phenyl ring of the sulfonyl substituent. The mol­ecular conformation features a weak C—H⋯N short contact and the crystal packing reveals a weak C—H⋯O hydrogen bond.

2-Iodo-3-(4-meth-oxy-anilino)-5,5-dimethyl-cyclo-hex-2-en-1-one

The cyclo­hexene ring in the title compound, C₁₅H₁₈INO₂, adopts a sofa conformation. The dihedral angle between the cyclo­hexene (through all ring atoms) and benzene rings is 63.3 (1)°. The mol­ecular conformation features an N—H⋯I short contact and the crystal packing features C—H⋯O hydrogen bonds.

Evaluation of emission of greenhouse gases from soils amended with sewage sludge

Increase in concentrations of various greenhouse gases and their possible contributions to the global warming are becoming a serious concern. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in C and N, as soil amendments could contribute to the increase in emission of greenhouse gases such as methane (CH(4)) and nitrous oxide (N(2)O) into the atmosphere. Therefore, evaluation of flux of various greenhouse gases from soils amended with sewage sludge is essential to quantify their release into the atmosphere. Two soils with contrasting properties (Candler fine sand [CFS] from Florida, and Ogeechee loamy sand [OLS] from Savannah, GA) were amended with varying rates (0, 24.7, 49.4, 98.8, and 148.3 Mg ha(-1)) of 2 types of sewage sludge (industrial [ISS] and domestic [DSS] origin. The amended soil samples were incubated in anaerobic condition at field capacity soil water content in static chamber (Qopak bottles). Gas samples were extracted immediately after amending soils and subsequently on a daily basis to evaluate the emission of CH(4), CO(2) and N(2)O. The results showed that emission rates and cumulative emission of all three gases increased with increasing rates of amendments. Cumulative emission of gases during 25-d incubation of soils amended with different types of sewage sludge decreased in the order: CO(2) > N(2)O > CH(4). The emission of gases was greater from the soils amended with DSS as compared to that with ISS. This may indicate the presence of either low C and N content or possible harmful chemicals in the ISS. The emission of gases was greater from the CFS as compared to that from the OLS. Furthermore, the results clearly depicted the inhibitory effect of acetylene in both soils by producing more N(2)O and CH(4) emission compared to the soils that did not receive acetylene at the rate of 1 mL g(-1) soil. Enumeration of microbial population by fluorescein diacetate (FDA) and most probable number (MPN) procedure at the end of 25-d incubation demonstrated a clear relationship between microbial activity and the emission of gases. The results of this study emphasize the need to consider the emission of greenhouse gases from soils amended with organic soil amendments such as sewage sludge, especially at high rates, and their potential contribution to global warming.

Effects of different rates of fly ash and sewage sludge mixture amendments on cation availability and their leachability

A leaching column study was conducted to evaluate the leaching of cations from soils amended with a mixture of (1:1) fly ash (FA) from Port Wentworth power plant, Savannah, GA: sewage sludge (SS) from President Street water pollution control plant, Savannah, GA. Two sets of soil-leaching columns (30-cm high and 7.5-cm diameter; 15 columns per soil) were prepared with a fine sandy soil from Florida (Candler fine sand; pH 6.8) and Georgia (Ogeechee loamy sand; pH 5.6). The top one inch of soil from each of these columns was amended (3 columns per treatment) with 1:1 mixture of SS and FA at either 0, 24.7, 49.4, 98.8 or 148.3 Mg ha(- 1) rate. After saturating the columns with deionized water, 18 cycles of intermittent leaching and drying was performed on weekly basis. Leaching of major cations and changes in ionic strength and pH were evaluated on half pore volume (220 mL) of leachate collected at each event. Results of this study indicated that leaching of cations increased rapidly up to the 3rd leaching event, and then rapidly decreased and the concentration of cations reached somewhat similar to that of unamended soil columns. Effects of soil type and rates of amendments on leaching of major cations along with changes of pH and ionic strength are discussed in this paper.

Effect of natural preservatives on the growth of histamine producing bacteria

Present study deals with the hampering of the growth of histamine producing bacteria (HPB), by using NaCl and spices which are easily available and cheaper cost wise. For this experiment, four strains of HPB viz. Vibrio parahaemolyticus, Bacillus cereus, Pseudomonas aeruginosa and Proteus mirabilis were tested against 1 to 10% concentrations of NaCl and 1 to 5% concentrations of natural preservatives (turmeric, ginger and garlic) in a basal medium. HPB showed different growth rates at different concentrations of NaCl and natural preservatives. V. parahaemolyticus, B. cereus and Ps. aeruginosa showed no growth at 10% concentration. When the HPB growth was tested with garlic, turmeric and ginger extracts, growth of all the bacteria was inhibited by garlic and turmeric extracts at 5% concentration. In ginger, V. parahaemolyticus, B. cereus and P. mirabilis were totally inhibited at 5% concentration. But Ps. aeruginosa showed very less growth at this concentration.

A comparison of anion concentration in surficial groundwater sampled from two types of water quality monitoring wells

Groundwater sampling for monitoring the presence and concentration of contaminants can be done using either depth integrated monitoring wells (MW) or depth specific multi-level sampling (MLS) wells. Depth specific multi-level sampling wells (MLS) are cost-effective, easy to install, and provide very detailed information about the vertical gradient in contaminant concentration. In contrast the MW sampling provides information on the presence of contaminant over large representative area. This study was conducted in two 33 ha blocks of a commercial citrus grove (Valencia orange trees on rough lemon rootstock) in a well drained Ashtabula fine sand (hyperthermic, uncoated, Typic Quartzipsamments). The depth to surficial groundwater at monitoring locations varied from 1.4 to 5.6 m, and the lateral groundwater flow rate was approximately 0.08 m d(-1). Anions were measured in groundwater sampled at 3-week intervals from four pair of MW and MLS in each of the two blocks. Since the screened portion of the MW in this study was placed in the top 150 cm of the surficial aquifer, the sampling parts of the MLS within this depth (2nd and 3rd ports) were considered for comparison. The results showed that the concentration of NO(-/3)-N, SO(2-/4) and Cl(-) in the MW samples were similar to the mean of the 2nd and 3rd port MLS sample concentrations over a one year period of sampling. Therefore, MLS sampling provides a technique to assess the groundwater quality very similar to that which can be obtainable by MW technique. In addition, the MLS provides useful information on the vertical gradient of solute concentrations thus allows evaluation of the short-term impacts of land management changes on solute concentrations in the very top layer of surficial aquifer in cost-effective manner.

Pelvic anatomy and MRI

An in-depth knowledge of the anatomy of the pelvis and pelvic sidewall is necessary before a gynaecologist can even contemplate making an initial examination and start management in cases of pelvic pathology or malignancy. This chapter provides basic information on gross pelvic anatomy structures that are of clinical relevance and discusses their correlation with medical imaging, especially magnetic resonance imaging (MRI). MRI is an ideal non-invasive technique in the assessment of normal anatomy and tissue characterization of pelvic pathology. The excellent soft-tissue contrast and the ability to direct multiplanar imaging and to demonstrate blood vessels without the use of intravenous contrast make MRI superior to other imaging modalities in the evaluation of pelvic abnormalities. The anatomical relation of the visceral organs, the differential zonal anatomy of the corpus uteri and the cyclical endometrial changes during the menstrual cycle are well depicted with MRI.

An evaluation of sources of nitrogen in shallow groundwater using (15)N abundance technique

A (15)N abundance technique was employed to identify the source of NO(3)-N in groundwater under three commercial citrus production sites in central Florida. Water samples were collected from 0 to 300 and 300 to 600 cm depths in the surficial aquifer and analyzed for NO(3)-N and delta N-15 (delta (15)N). Groundwater samples were also collected in a residential area adjacent to one of the citrus groves and analyzed for NO(3)-N and delta (15)N. The delta (15)N values were in the range of (+)1 to (+)10% in both depths underneath the citrus groves. The range of delta (15)N measured in this study represents the range expected for groundwater that was impacted by NO(3)-N originated from mineralization of organic N from the soil as well as from the crop residue. There are occasional high delta (15)N values which are indicative of the effects of NH(3) volatilization losses of applied fertilizer N. The range of delta (15)N values for groundwater samples collected from the residential area adjacent to the citrus groves was very similar to that from the groundwater underneath the citrus groves. Thus, the source of NO(3)-N that impacted the groundwater under the citrus groves also impacted the groundwater in the adjacent residential area.

Adsorption/desorption of copper by a sandy soil amended with various rates of manure, sewage sludge, and incinerated sewage sludge

Organic amendments are sometimes applied to agricultural soils to improve the physical, chemical, and microbiological properties of the soils. The organic fractions in these soil amendments also influence metal reaction, particularly the adsorption and desorption of metals, which, in turn, determine the bioavailability of the metals and hence their phytotoxicities. In this study, a Quincy fine sandy (mixed, mesic, Xeric Torripsamments) soil was treated with 0 to 160 g kg(-1) rates of either manure, sewage sludge (SS), or incinerated sewage sludge (ISS) and equilibrated in a greenhouse at near field capacity moisture content for 100 days. Following the incubation period, the soil was dried and adsorption of copper (Cu) was evaluated in a batch equilibration study at either 0, 100, 200, or 400 mg L(-1) Cu concentrations in a 0.01M CaCl2 solution. The desorption of adsorbed Cu was evaluated by three successive elutions in 0.01M CaCl2. Copper adsorption increased with an increase in manure rates. At the highest rate of manure addition (160 g kg(-1) soil), Cu adsorption was two-fold greater than that by the unamended soil at all rates of Cu additions. With increasing rates of Cu additions, the adsorption of Cu decreased from 99.4 to 77.6% of Cu applied to the 160 g kg(-1) manure amended soil. The desorption of Cu decreased with an increase in rate of manure amendment. Effects of sewage sludge amendments on Cu adsorption were somewhat similar to those as described for manure additions. Likewise, the desorption of Cu was the least at the high rate of SS addition (160 g kg(-1)), although at the lower rates there was not a clear indication of the rate effects. In contrast to the above two amendments, the ISS amendment had the least effect on Cu adsorption. At the highest rate of ISS amendment, the Cu adsorption was roughly 50% of that at the similar rate of either manure or SS amendments, across all Cu rates.

Soil pH and anion abundance affects on copper adsorption

Copper (Cu) input to agricultural soils results from Cu containing pesticides and or that in soil amendments, such as manure or sewage sludge. Soil and soil solution properties influence the adsorption and desorption of Cu by the soil, which in turn determines its plant availability and/or phytotoxicities. Effects of different anion enrichment in the equilibrium solution on Cu adsorption by different soils (pH range of 6.2-9.9) were investigated in this study over a range of Cu concentrations. With Cu concentrations in the range of 0-100 mg L(-1) in the equilibration solution, 95-99% of applied Cu was adsorbed by all three soils. The adsorption of Cu was similar regardless of using either 0.01 M CaCl2 or Ca(NO3)2 as the equilibration solution. When the Cu concentration in the equilibration solution was further increased in the range of 500-2000 mg L(-1), the adsorption of Cu decreased from 60 to 24% of applied Cu in two soils with pH 6.2-7.9. In a high pH soil (pH=9.9), the Cu adsorption decreased from 77 to 34%. Addition of incinerated sewage sludge (ISS) to a Palouse silt loam soil (pH = 6.2) increased the Cu adsorption as compared to that by unamended soil. This was, in part, due to an increase in the soil suspension pH with ISS amendment.

Elemental transport and distribution in soils amended with incinerated sewage sludge

Sewage sludge (SS) is the major solid waste of sewage and wastewater treatment plants in cities around the world. Even though treated effluent water from wastewater treatment plants are utilized for irrigation, disposal of sewage sludge is becoming a serious problem. This is due to its high content of certain heavy metals still posing threat of accumulation in plants and groundwater contamination when it is used as soil amendment or disposed in landfills. Water treatment plants incinerate the dewatered activated sewage sludge (ISS) and dissolve the ash in water to store in ash ponds for long-term storage (WISS). A study was undertaken to evaluate the transport and leaching potential of various elements and their distribution within soil columns amended with various rates of ISS. Results of this study indicates that ISS from wastewater treatment plants can be used as soil amendment on agricultural lands at low to medium rates (< or = 100 Mg ha(-1)) without causing potential loading of metals into groundwater.

Fate of nitrate and bromide in an unsaturated zone of a sandy soil under citrus production

Understanding water and nutrient transport through the soil profile is important for efficient irrigation and nutrient management to minimize excess nutrient leaching below the rootzone. We applied four rates of N (28, 56, 84, and 112 kg N ha(-1); equivalent to one-fourth of annual N rates being evaluated in this study for bearing citrus trees), and 80 kg Br- ha(-1) to a sandy Entisol with >25-yr-old citrus trees to (i) determine the temporal changes in NO3-N and Br- distribution down the soil profile (2.4 m), and (ii) evaluate the measured concentrations of NO3-N and Br- at various depths with those predicted by the Leaching Estimation and Chemistry Model (LEACHM). Nitrate N and Br concentrations approached the background levels by 42 and 214 d, respectively. Model-predicted volumetric water content and concentrations of NO3-N and Br- at various depths within the entire soil profile were very close to measured values. The LEACHM data showed that 21 to 36% of applied fertilizer N leached below the root zone, while tree uptake accounted for 40 to 53%. Results of this study enhance our understanding of N dynamics in these sandy soils, and provide better evaluation of N and irrigation management to improve uptake efficiency, reduce N losses, and minimize the risk of ground water nitrate contamination from soils highly vulnerable to nutrient leaching.

Nitrogen partitioning in Heterorhabditis bacteriophora-infected hosts and the effects of nitrogen on attraction/repulsion

Entomopathogenic nematode behavior is affected by the condition of their infected hosts. We hypothesized that nitrogen compounds released from infected hosts may be one factor affecting entomopathogenic nematode host-finding and infection behaviors. Our objectives were to (1) investigate the partitioning of nitrogen in Galleria mellonella (L.) infected by Heterorhabditis bacteriophora Poinar and (2) determine attraction and repulsion of H. bacteriophora to various quantities of nitrogen (ammonia). Volatile (ammonia), organic, and inorganic nitrogen forms were monitored during the course of infection. Approximately 0.052 mg of nitrogen was released from a single infected host as volatile ammonia. Most of the ammonia release was detected within the first 3 days postinoculation. Organic nitrogen increased during the course of infection, whereas inorganic nitrogen decreased. The net nitrogen change in the infected host consisted of a loss of approximately 47 mg, most of which was lost within the 1st week of infection. Accelerated loss of nitrogen early in the infection process was likely correlated with activity and growth of bacterial symbionts. Increased organic nitrogen was likely associated with nematode reproduction within the host. Attraction or repulsion of H. bacteriophora to nitrogen (ammonium hydroxide) was measured on agar quadrant plates. Nematodes were attracted to 16 and 160 microg of nitrogen and repelled by concentrations of 1600 and 8000 microg. Our data indicate that nitrogen released from H. bacteriophora-infected hosts attracts nematodes at lower levels (early in the infection) and repels them at higher concentrations (later in the infection process).

Audit of new long-stay patients in Permai Mental Hospital, Johor

We report a cross-sectional descriptive study of 90 new long-stay patients (NLS) (i.e. those who had been resident for six months to three years in Permai Mental Hospital, Johor) and studied from April to June, 1995. The age of this sample ranged from 18 to 85 years. Two subgroups were observed (i.e. younger NLS patients aged 18 to 34 years and older NLS patients aged 35 to 85 years). Among the younger NLS patients, the commonest diagnosis was schizophrenia (51.2%), followed by mental retardation with related problems (24.4%). Sixty-one percent of these younger patients had a history of serious violence or dangerous behaviour. Older NLS patients were likely to have a diagnosis of schizophrenia (79.6%), followed by mood disorder (6.1%) and dementia (4.1%). Forty seven percent of these older group had history of danger to others and 57.1% were at moderate or severe risk of non-deliberate self-harm. Focusing on the schizophrenic patients, all of them had some form of psychopathology, either positive, negative or general symptoms and about one-fourth were assessed to pose a risk for aggression.