Predicting forest floor and woody fuel consumption from prescribed burns in southern and western pine ecosystems of the United States.

We present pre-burn biomass and consumption data from 60 prescribed burns in the southeastern and western United States. The datasets include pre-burn biomass in Mg/ha by fuel category: herbaceous fuels, shrubs, 1-hr, 10-hr, 100-hr, 1000-hr, 10,000-hr, and > 10,000-hr downed wood, litter and duff. Pre-burn depth (cm) and reduction (cm) are provided for litter and duff layers. Day-of-burn fuel moistures and weather are also listed by site.

Dynamic response mitigation of floating wind turbine platforms using tuned liquid column dampers.

In this paper, we experimentally study and compare the effects of three combinations of multiple tuned liquid column dampers (MTLCDs) on the dynamic performance of a model floating tension-leg platform (TLP) structure in a wave basin. The structural stability and safety of the floating structure during operation and maintenance is of concern for the performance of a renewable energy device that it might be supporting. The dynamic responses of the structure should thus be limited for these renewable energy devices to perform as intended. This issue is particularly important during the operation of a TLP in extreme weather conditions. Tuned liquid column dampers (TLCDs) can use the power of sloshing water to reduce surge motions of a floating TLP exposed to wind and waves. This paper demonstrates the potential of MTLCDs in reducing dynamic responses of a scaled TLP model through an experimental study. The potential of using output-only statistical markers for monitoring changes in structural conditions is also investigated through the application of a delay vector variance (DVV) marker for different conditions of control for the experiments.

Association between glycosylated hemoglobin and cancer risk: a New Zealand linkage study.

BACKGROUND: The purpose of this study was to examine the relationship between glycosylated hemoglobin (HbA(1c)) level and subsequent cancer risk. MATERIAL AND METHODS: HbA(1c) measurements were made on blood samples of participants in a hepatitis B (HB) screening program (1999-2001). Cancer incidence was determined by linkage to cancer registrations and hospitalization records to the end of 2004. Participants previously diagnosed with diabetes or cancer were excluded. Hazard ratios (HR) and 95% confidence intervals (CIs) were estimated using Cox regression. RESULTS: Among the 46 575 participants (70% Maori, 12% Pacific, 5% Asian and 12% Other), 634 cancer cases were observed. For all cancers combined, a significant increased risk was found in persons with moderately elevated HbA(1c) levels (6%-6.9%) (HR 1.40, 95% CI: 1.11-1.76), with a smaller increased risk in persons with highly elevated levels (> or =7%) (HR 1.09, 95% CI: 0.80-1.48) as compared with persons having low HbA(1c) levels (<6%). The HRs for respiratory cancers were 2.27 (95% CI: 1.34-3.86) for the moderate HbA(1c) category and 1.58 (95% CI: 0.77-3.26) for the upper HbA(1c) category. For endometrial cancers, the HRs were 4.05 (95% CI: 1.10-14.88) and 5.07 (95% CI: 1.20-21.31), respectively. For other cancer sites, no significantly increased risks were found. CONCLUSIONS: These findings are consistent with other evidence that abnormal glucose metabolism may be associated with an increased risk of some cancers.

Infant-furniture-related injuries among preschool children in New Zealand, 1987-1996.

OBJECTIVE: To describe the epidemiology of infant-furniture-related fatalities and hospitalizations in New Zealand, for children aged 0-4 years. METHODS: Infant-furniture-related deaths and hospitalizations were selected from the New Zealand Health Information Service databases for the 10-year period 1987-1996. Intentional injuries were excluded. RESULTS: Forty-three fatalities were identified. Twenty-two fatalities (51%) occurred in cots, while 13 (30%) occurred in beds. Other products involved were prams, push chairs, high chairs, car seats, portable cots and walkers. A total of 1679 infants were hospitalized through infant-furniture-related injuries. Increasing trends in hospitalizations for baby walkers, beds and bunks were observed. CONCLUSIONS: On average, four infants die each year from injuries related to infant furniture, and hospitalizations from injuries associated with infant furniture use are increasing. Mandatory standards are one measure to reduce these numbers, but education is also necessary.

Adolescent injury morbidity in New Zealand, 1987-96.

OBJECTIVES: Adolescents are over-represented in injury statistics. New Zealand is privileged in having a hospital discharge database allowing for analysis of non-fatal injury data at a national level. An epidemiological description of adolescent injury morbidity is provided and options for prevention are discussed. METHOD: People aged 15-19 years admitted to hospital for their injuries in the period 1 987-96 were identified from the New Zealand Health Information Service morbidity data files. The manner, causes, and nature of injury were examined. Injury prevention strategies were reviewed. RESULTS: The incidence of hospitalised injury was 1,886 per 100,000 person years. The victims were male (70%). The leading causes of injury were road traffic crashes, sports injuries, and self poisoning. The most common injury diagnoses were head injuries (29%) and limb fractures (21%). Road traffic crashes produced the highest proportion of serious injuries. CONCLUSIONS: Road traffic crashes, sports injuries, and self inflicted poisoning, stood out as areas with the greatest potential for reducing the burden of injury in late adolescence. Graduated driver licensing shows promise as an injury prevention measure but remains inadequately implemented. Policies to reduce self inflicted poisoning are of unknown efficacy, and evidence is awaited on the effectiveness of measures to reduce injury in sport.

Shopping trolley-related injuries to children in New Zealand, 1988-97.

OBJECTIVE: To describe the epidemiology of shopping trolley related injuries (fatalities and hospitalizations) to children in New Zealand prior to the introduction of a voluntary standard for shopping trolleys. METHODOLOGY: To identify cases, a key word search was conducted of national mortality and hospitalization databases for the years 1988-97. Cases were limited to children under 15 years of age. RESULTS: For the 10 year period investigated, 282 hospitalizations and no fatalities were identified. A significant increasing trend for hospitalizations was detected (chi2 = 17.6, 1 d.f.; P < 0.001). Ninety-two per cent of children hospitalized were aged under 5 years and two-thirds were aged 2 years or younger. Ninety per cent of injuries resulted from falls from trolleys, 84% of injuries were to the head or face and 22% were rated serious (AIS-3) on the Abbreviated Injury Scale. CONCLUSIONS: The incidence of injuries associated with shopping trolleys increased between 1988 and 1997. Following the introduction of a voluntary standard for shopping trolleys in 1999, which included specifications for child harnesses, trends in injury should be monitored.

Identifying possible contingencies during descriptive analyses of severe behavior disorders.

Contingencies of reinforcement involve, in part, relations between behavior and subsequent environmental events. In this study we observed 11 individuals with developmental disabilities and severe behavior problems while they interacted with their primary care providers in simulated environments (hospital therapy rooms). We compared the probability of obtaining attention, escape from instructional demands, or access to materials following instances of problem behavior with the background probability of those events. However, the focus of our analysis was the evaluation of comparative probabilities ("contingency values") in the context of relevant establishing operations such as diverted attention, instructional demands, and restricted access to materials. Results showed that the method was useful in identifying relations between behavior and subsequent environmental events. Implications for linking descriptive and functional analyses are discussed, and difficulties in identifying naturally occurring contingencies are considered.

Compliance of Dunedin school playground equipment with the New Zealand playground standard.

OBJECTIVE: Injuries resulting from falls from playground equipment are a public health concern in New Zealand. Like many other countries, New Zealand has a safety standard aimed at reducing the incidence and severity of these injuries by limiting the height from which children can fall from playground equipment and requiring the provision of impact-absorbing surfaces beneath equipment from which falls are possible. The purpose of this study was to examine progress towards achieving compliance with these requirements in Dunedin school playgrounds. METHODS: Sixty-two schools were audited over the summer of 1997/98 and information recorded on equipment type, maximum fall height, surface type, and depth of loose-fill surface materials. Comparisons were made with audits conducted in 1989 and 1981. RESULTS: Substantial increases in the amount of playground equipment and in the provision of impact-absorbing surfaces were observed. A small increase in compliance with the requirement that the maximum fall height of equipment not exceed 2.5 metres was also observed. CONCLUSIONS: Any gains in safety achieved through increased compliance with the height and surface requirements of the New Zealand Standard have been counteracted by the substantial increase in the amount of equipment available in playgrounds. IMPLICATIONS: A more drastic measure is needed to achieve a meaningful reduction in the incidence of injury following falls from playground equipment.

Child injury morbidity in New Zealand, 1987-1996.

OBJECTIVES: New Zealand is one of a small number of countries that has a national hospital discharge database. The aim of this study was to use these data to provide an epidemiological description of child injury morbidity and to discuss options for prevention. METHODOLOGY: Using national data, all public hospital admissions for the fiscal year 1995/6 were identified and grouped according to cause. This allowed identification of all children (0-14 years) hospitalized for injury in the period 1987-1996. Causes of injury, diagnoses and injury severity were examined in four age groups. RESULTS: Injury was the second leading cause of public hospital admissions. Children were hospitalized with injury at the rate of 1333 per 100 000 person-years. The victims were predominantly male (61%). In all age groups, falls were the leading cause of morbidity. 'Striking events', motor vehicle traffic crashes and poisoning were also major contributors to the child injury toll. The commonest injury diagnosis was a fracture of the upper limb (25%), followed by intracranial injury (18%). CONCLUSIONS: The leading causes of injury morbidity were noted to differ from previously reported leading causes of injury mortality. Review of the data in light of research literature suggests the need for policy changes to make alternatives to motor vehicle transportation safer and to encourage increased use of child restraints in order to reduce road traffic trauma. Legislation requiring child-resistant packaging for all toxic medications and household products is necessary to reduce rates of child poisoning. Further research is required on policies concerning playground equipment heights and surfacing requirements, and on interventions for hot water scalds.

Stage-specific and differential expression of gap junctions in the mouse ovary: connexin-specific roles in follicular regulation.

Gap junction communication plays an essential role in follicle growth. Immunocytochemistry and confocal microscopy were used to examine the expression of gap junction connexins of the alpha and beta subfamilies in follicles from primordial to preovulatory stages in the ovaries of prepubertal and adult mice. Connexin-specific antibodies detected alpha(1), alpha(4), alpha(6), beta(1), beta(2) and beta(4) connexins within follicles. In adult ovaries connexin immunolabelling was stronger in larger (more mature) follicles than it was in smaller follicles, with comparatively reduced labelling detected in prepubertal ovaries. In healthy follicles, labelling for alpha subfamily connexins was detected between granulosa cells, whereas labelling for beta subfamily connexins was found in the theca. Labelling for beta subfamily connexins and alpha(4) connexin (preantral stage) was detected on the oocyte surface membrane. In atretic follicles, labelling for beta(4) connexin appeared between the granulosa cells. These results demonstrate that alpha and beta connexin subfamilies are segregated to separate cellular compartments in the mouse follicle. The results are discussed in the light of possible roles for differential gap junctional communication in the regulation of folliculogenesis, oocyte maturation and atresia.

Crystal structure of human GM2-activator protein with a novel beta-cup topology.

GM2 activator protein (GM2-AP) belongs to a small group of non- enzymatic lysosomal proteins that act as cofactors in the sequential degradation of gangliosides. It has been postulated that GM2-AP extracts single GM2 molecules from membranes and presents them in soluble form to beta-hexosaminidase A for cleavage of N-acetyl-d-galactosamine and conversion to GM3. The high affinity of GM2-AP for GM2 is based on specfic recognition of the oligosaccharide moiety as well as the ceramide lipid tail. Genetic defects in GM2-AP result in an atypical form of Tay-Sachs disease known as variant AB GM2 gangliosidosis. The 2.0 A resolution crystal structure of GM2-AP reported here reveals a previously unobserved fold whose main feature is an eight-stranded cup-shaped anti-parallel beta-pleated sheet. The striking feature of the GM2-AP structure is that it possesses an accessible central hydrophobic cavity rather than a buried hydrophobic core. The dimensions of this cavity (12 Ax14 Ax22 A) are suitable for binding 18-carbon lipid acyl chains. Flexible surface loops and a short alpha-helix decorate the mouth of the beta-cup and may control lipid entry to the cavity.

Child injury mortality in New Zealand 1986-95.

OBJECTIVES: Injury has been described as 'the last major plague of the young'. We provide an epidemiological description of injury, as a leading cause of death in New Zealand, and identify options for prevention. METHODS: We identified all deaths due to any cause for the period 1986-95 from the national data and calculated the potential years of life lost for each death. For the same period, we identified all injury deaths for children aged 0-14 years. Causes of injury were examined in four age groups. RESULTS: In the population as a whole, injury was the fourth leading cause of death and the leading cause of potential years of life lost. Injury killed children at the rate of 16.8 per 100,000 person-years. The victims were predominantly male (62%) and 52% were under 5 years of age. In infancy (<1 year of age), suffocation was the leading cause of injury mortality. From 1 to 14 years of age, motor vehicle traffic incidents were the leading cause of mortality. CONCLUSIONS: Motor vehicle traffic incidents, drowning, suffocation and suicide stood out as areas with the greatest potential for reducing child injury mortality. A number of existing prevention strategies show promise (e.g. child restraints), others are inadequately implemented (e.g. swimming pool fencing) or are of unknown efficacy (e.g. government suicide prevention policies). Strategies to reduce infant suffocation and child non-traffic pedestrian deaths remain to be developed and tested.

In vitro maturation of oocytes.

Only about 400 of the one million oocytes present at birth will be ovulated, while the rest will die by atresia. The ability to rescue oocytes destined to die and mature them in vitro would provide invaluable information about folliculogenesis and oocyte maturation, and could provide oocytes for infertile women. In vitro maturation (IVM) is challenging in the human because folliculogenesis is a lengthy process encompassing many complex cellular changes in the oocyte and its surrounding follicle cells. A few live births have resulted from the maturation and fertilization of immature human oocytes aspirated from small antral follicles. Furthermore, it is possible to grow primordial follicles to pre-antral stages in slices of ovarian tissue, and support antrum formation in isolated pre-antral follicles. However, we are still a considerable way from growing and maturing pre-antral follicles to pre-ovulatory stages in vitro. The importance of the follicular environment for producing a healthy and developmentally competent oocyte is illustrated by the oocyte's susceptibility to errors during meiosis. This counsels considerable caution in the development of IVM for clinical application.

Specialist registrar training in obstetrics and gynaecology: have we got it wrong?

The introduction of the Calman proposals for radical reform of the training of young doctors is now nearly 3 years past. Obstetrics and gynaecology was one of the first major specialties to go through the convulsions of transition and it has emerged on the other side well organized and in tune with the requirements of the reforms, but just how are they perceived by the trainees and trainers?

Effects of follicle-stimulating hormone and serum substitution on the in-vitro growth of human ovarian follicles.

In-vitro maturation (IVM) of human ovarian follicles and oocytes could benefit infertile women, and allow the development of in-vitro systems for the study of human follicular development. Little is known about the initiation of growth of primordial follicles and the regulation of early folliculogenesis. An ovarian tissue-slice culture system was used to examine the effects of media composition, follicle stimulating hormone (FSH) and serum substitution on the development of small human follicles in vitro. Human ovarian cortex biopsies were cut into small pieces and cultured for 5, 10 or 15 days. Control (non-cultured) and cultured tissue was fixed, serially sectioned, and stained. The follicles contained within the tissue pieces were counted, measured, and assessed for stage of development and viability. Comparison of the ability of alpha-minimum essential medium (alpha-MEM), Waymouth's, or Earle's balanced salt solution (EBSS) culture media (all with 10% human serum) to support follicle growth demonstrated significantly increased initiation and growth of follicles in alpha-MEM during the first 10 days of culture. The supplementation of alpha-MEM with 300 mIU/ml FSH significantly reduced levels of atresia and increased the mean diameter of healthy follicles. Follicles in tissue cultured for 10 days with human serum albumin and ITS (insulin/transferrin/selenium mix) were significantly larger, more developed and showed significantly less atresia than those cultured with serum alone. Primordial to small preantral follicles can be grown under serum-substituted conditions in tissue-slice culture, and are responsive to FSH, which is thought to be acting mainly as a survival factor at these early stages.

Fixed-time schedules attenuate extinction-induced phenomena in the treatment of severe aberrant behavior.

We compared the effects of extinction (EXT) and fixed-time (FT) schedules as treatment for severe problem behavior displayed by 3 individuals with developmental disabilities. First, functional analyses identified the reinforcers maintaining aberrant behavior for all 3 individuals. Next, EXT and FT schedules were compared using a multielement design. During EXT, the reinforcer maintaining problem behavior was withheld. During FT, the reinforcers were presented response independently at preset intervals. Results showed that FT schedules were generally more effective than EXT schedules in reducing aberrant behavior. FT schedules may be used in situations when extinction-induced phenomena are problematic.

New folds of plant lectins.

Among the crystal structures of lectins determined recently, three--snowdrop lectin, jacalin and amaranthin--represent new lectin families. Their polypeptide folds share remarkably similar features and consist exclusively of beta structure. Autonomously folded beta-sheet subdomains, inter-related by a pseudothreefold symmetry, assemble to form beta-prism or beta-barrel structures which are stabilized by a hydrophobic core.

Role of aromatic amino acids in carbohydrate binding of plant lectins: laser photo chemically induced dynamic nuclear polarization study of hevein domain-containing lectins.

Carbohydrate recognition by lectins often involves the side chains of tyrosine, tryptophan, and histidine residues. These moieties are able to produce chemically induced dynamic nuclear polarization (CIDNP) signals after laser irradiation in the presence of a suitable radical pair-generating dye. Elicitation of such a response in proteins implies accessibility of the respective groups to the light-absorbing dye. In principle, this technique is suitable to monitor surface properties of a receptor and the effect of ligand binding if CIDNP-reactive amino acids are affected. The application of this method in glycosciences can provide insights into the protein-carbohydrate interaction process, as illustrated in this initial study. It focuses on a series of N-acetylglucosamine-binding plant lectins of increasing structural complexity (hevein, pseudohevein, Urtica dioica agglutinin and wheat germ agglutinin and its domain B), for which structural NMR- or X-ray crystallographic data permit a decision of the validity of the CIDNP method-derived conclusions. On the other hand, the CIDNP data presented in this study can be used for a rating of our molecular models of hevein, pseudohevein, and domain B obtained by various modeling techniques. Experimentally, the shape and intensity of CIDNP signals are determined in the absence and in the presence of specific glycoligands. When the carbohydrate ligand is bound, CIDNP signals of side chain protons of tyrosine, tryptophan, or histidine residues are altered, for example, they are broadened and of reduced intensity or disappear completely. In the case of UDA, the appearance of a new tryptophan signal upon ligand binding was interpreted as an indication for a conformational change of the corresponding indole ring. Therefore, CIDNP represents a suitable tool to study protein-carbohydrate interactions in solution, complementing methods such as X-ray crystallography, high-resolution multidimensional nuclear magnetic resonance, transferred nuclear Overhauser effect experiments, and molecular modeling.

Carbohydrate-protein interaction studies by laser photo CIDNP NMR methods.

The side chains of tyrosine, tryptophan and histidine are able to produce CIDNP (Chemically Induced Dynamic Nuclear Polarization) signals after laser irradiation in the presence of a suitable radical pair-generating dye. Elicitation of such a response in proteins implies surface accessibility of the respective groups to the light-absorbing dye. In principle, this technique allows the monitoring of the effect of ligand binding to a receptor and of site-directed mutagenesis on conformational aspects of any protein if CIDNP-reactive amino acids are involved. The application of this method in glycosciences can provide insights into the protein-carbohydrate interaction process, as illustrated in this initial model study for several N-acetyl-glucosamine-binding lectins of increasing structural complexity as well as for a wild type bacterial sialidase and its mutants. Experimentally, the shape and intensity of CIDNP signals are determined in the absence and in the presence of specific glycoligands. When the carbohydrate is bound, CIDNP signals of side chain protons of tyrosine, tryptophan or histidine residues can be broadened and of reduced intensity. This is the case for hevein, pseudo-hevein, the four hevein domains-containing lectin wheat germ agglutinin (WGA) and the cloned B-domain of WGA 1 (domB) representing one hevein domain. This response indicates either a spatial protection by the ligand or a ligand-induced positioning of formerly surface-exposed side chains into the protein's interior part, thereby precluding interaction with the photo-activated dye. Some signals of protons from the reactive side chains can even disappear when the lectin-ligand complexes are monitored. The ligand binding, however, can apparently also induce a conformational change in a related lectin that causes the appearance of a new signal, as seen for Urtica dioica agglutinin (UDA) which consists of two hevein domains. Additionally, the three CIDNP-reactive amino acids are used as sensors for the detection of conformational changes caused by pH variations or by deliberate amino acid exchanges, as determined for the isolectins hevein and pseudo-hevein as well as for the cloned small sialidase of Clostridium perfringens and two of its mutants. Therefore, CIDNP has proven to be an excellent tool for protein-carbohydrate binding studies and can be established in glycosciences as a third biophysical method beside X-ray-crystallography and high-resolution multidimensional NMR studies which provides reliable information of certain structural aspects of carbohydrate-binding proteins in solution.

Crystallization and preliminary X-ray characterization of GM2-activator protein.

G(M2) activator protein is a glycolipid transfer protein cofactor necessary for the hydrolytic degradation of G(M2) ganglioside by beta-hexosaminidase A. Its absence in human tissue results in symptoms of type AB Tay-Sachs disease. The protein prepared by recombinant techniques using an E. coli expression system, has been crystallized by the vapor-diffusion technique. The crystals are well ordered and belong to the orthorhombic space group P2(1)2(1)2(1). The unit-cell dimensions are a = 42.40, b = 39.82, c = 113.61 A. One molecule is contained in the asymmetric unit.