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PubMed2007

Structural characteristics of Abies mariesii saplings in a snowy subalpine parkland in central Japan.

Structural characteristics of Abies mariesii M.T. Mast. saplings growing in sun and shade in a snowy subalpine parkland in central Japan were assessed to infer how saplings acclimate to suppression by larger individuals in a conifer clump and to extremely snowy conditions. Sun and shade saplings produced structurally different current-year shoots, and allocated biomass to needles and stem differently. Compared with sun saplings, shoots of shade saplings had lower needle mass per unit shoot size, which indicates less dense needle packing and more effective use of the limited available light by avoiding mutual shading among needles. Biomass allocation within lateral branches also differed between sun and shade saplings. Compared with sun saplings, needle mass was a smaller proportion of total branch mass in shade saplings although shade saplings retained needles for longer, thereby compensating, in part, for their lower annual production of needles. Thus shade saplings incur a high mechanical cost to support their low-light acclimated, conspicuously flattened crowns in this snowy habitat. Suppressed saplings are an important component of the persistent conifer clumps in snowy subalpine parklands. The observed structural characteristics of A. mariesii saplings, which ensure high shade- and snow-tolerance, contribute to the dominance of the species in snowy subalpine regions in Honshu, Japan.

Abies↗
PubMedDate not supplied

Evaluating progress toward closed forest models based on fluxes of carbon, water and nutrients.

Closed system models are defined as mathematical models of systems having specified boundaries within which all flows into and out of the system are accounted for. Closure is obtained experimentally when we can measure all the flows and do not depend on residuals. The meeting on which this volume is based discussed a range of models and approaches to modeling, and the possibility of achieving closure. There was general agreement that we can develop closed system models of the water balance, carbon cycle and nutrient fluxes at the stand level. Confidence in our ability to account for all the flows is greatest for water, decreasing progressively for carbon and nutrients. The priority areas for research on the carbon balance are belowground processes, foliage dynamics and respiration. The problems requiring particular attention in relation to the water balance are the measurement of interception losses, lateral flow in the soil and evaporation from snow. Areas warranting particular research attention in relation to nutrient fluxes through forest stands are the rates, and the controls on rates, of nutrient uptake by trees, and rates of mineralization with emphasis on the importance of microbial processes at the ecosystem level. Most models are written for uniform conditions. Forests are not uniform so the problem of heterogeneity, and how to deal with it in models, requires considerable attention, as does the question of how to scale up, to deal with large areas. There are a great many forest models of all types and the continual development of new ones may not be an effective use of research resources. There is a need for some assessment of the range of models currently existing, or under development, and for moves toward a directed strategy of model structure and development.

Journal Article↗
PubMed1992

A model for health intervention.

A Primary Health Care Programme was initiated in a squatter settlement of Karachi with the aim of increasing the awareness regarding the importance of hygiene, immunization, oral rehydration (ORS), nutrition, and so on. A minimum of four resource personnel were able to reach 700 individuals by means of a 'snow-balling' effect. Primary Health Care Workers from the area were required to provide health education to mothers in the Community. A post-intervention survey revealed health education (intervention) was successful in modifying the approach of home-management of diarrhoea, fever and respiratory tract infections. Literacy also influenced home-management of diarrhoea and fever. Thus, health education not only changed the awareness and knowledge of the Community, but also successfully altered health practices which is reflected in reduced incidence of these diseases.

Health Education↗
PubMed1991

Rescue and maturation in vitro of follicular oocytes collected from nondomestic felid species.

The potential for rescuing immature oocytes from the ovaries of females of rare felid species which die or undergo medical ovariohysterectomy was evaluated. Ovaries were recovered from 13 species representing 35 individuals in good-to-poor health. Although the majority of females were 10 yr of age or older and in fair-to-poor health, a total of 846 oocytes were recovered of which 608 (71.9%) were classified as fair-to-excellent quality. One hundred of these oocytes were used for initial maturation classification and as parthogenetic controls. Overall, of the 508 fair-to-excellent quality oocytes placed in culture, 164 (32.3%) matured to metaphase II in vitro. For species in which 3 or more individuals yielded oocytes, mean oocyte maturation rates were as follows: 36.2%, tiger; 27.9% leopard; and 8.3%, cheetah. In vitro insemination of oocytes resulted in fertilization (2 polar bodies, 2 pronuclei, or cleavage) rates of 9.1% to 28.6% (leopard) using homologous fresh spermatozoa and 4.0% (lion) to 40.0% (puma) using homologous frozen-thawed spermatozoa. Inseminations using heterologous (domestic cat) spermatozoa also resulted in fertilized oocytes in the tiger, leopard, snow leopard, puma, serval, and Geoffroy's cat (range in fertilization rate, 5.0% for leopard to 46.2% for puma). Cleaved embryos resulted from the insemination of leopard oocytes with homologous sperm (n = 1 embryo) and puma oocytes with domestic cat sperm (n = 3 embryos). These results demonstrate that immature ovarian oocytes from rare felid species can be stimulated to mature in vitro despite an excision-to-culture interval as long as 36 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Comparative aspects of steroid hormone metabolism and ovarian activity in felids, measured noninvasively in feces.

Noninvasive fecal assays were used to study steroid metabolism and ovarian activity in several felid species. Using the domestic cat (Felis catus) as model, the excretory products of injected [14C]estradiol (E2) and [14C]progesterone (P4) were determined. Within 2 days, 97.0 +/- 0.6% and 96.7 +/- 0.5% of recovered E2 and P4 radioactivity, respectively, was found in feces. E2 was excreted as unconjugated estradiol and estrone (40%) and as a non-enzyme-hydrolyzable conjugate (60%). P4 was excreted primarily as non-enzyme-hydrolyzable, conjugated metabolites (78%) and as unconjugated pregnenolone epimers. A simple method for extracting fecal steroid metabolites optimized extraction efficiencies of the E2 and P4 excretion products (90.1 +/- 0.8% and 87.2 +/- 1.4%, respectively). Analysis of HPLC fractions of extracted fecal samples from the radiolabel-injected domestic cats revealed that E2 immunoreactivity coincided primarily with the unconjugated metabolized [14C]E2 peak, whereas progestogen immunoreactivity coincided with a single conjugated epimer and multiple unconjugated pregnenolone epimers. After HPLC separation, similar immunoreactive E2 and P4 metabolite profiles were observed in the leopard cat (F. bengalensis), cheetah (Acinonyx jubatus), clouded leopard (Neofelis nebulosa), and snow leopard (Panthera uncia). Longitudinal analyses demonstrated that changes in fecal E2 and P4 metabolite concentrations reflected natural or artificially induced ovarian activity. For example, severalfold increases in E2 excretion were associated with overt estrus or exogenous gonadotropin treatment, and elevated fecal P4 metabolite concentrations occurred during pregnant and nonpregnant (pseudopregnant) luteal phases. Although overall concentrations were similar, the duration of elevated fecal P4 metabolites during pseudopregnancy was approximately half that observed during pregnancy. In summary, steroid metabolism mechanisms appear to be conserved among these physically diverse, taxonomically related species. Results indicate that this hormone-monitoring approach will be extremely useful for elucidating the hormonal regulatory mechanism associated with the reproductive cycle, pregnancy, and parturition of intractable and endangered felid species.

Animals↗
PubMed1993

Bacterial ice nucleation: significance and molecular basis.

Several bacterial species are able to catalyze ice formation at temperatures as warm as -2 degrees C. These microorganisms efficiently catalyze ice formation at temperatures much higher than most organic or inorganic substances. Because of their ubiquity on the surfaces of frost-sensitive plants, they are responsible for initiating ice formation, which results in frost injury. The high temperature of ice catalysis conferred by bacterial ice nuclei makes them useful in ice nucleation-limited processes such as artificial snow production, the freezing of some food products, and possibly in future whether modification schemes. The rarity of other ice nuclei active at high subfreezing temperature, and the ease and sensitivity with which ice nuclei can be quantified, have made the use of a promoterless bacterial ice nucleation gene valuable as a reporter of transcription. Target genes to which this promoter is fused can be used in cells in natural habitats. Warm-temperature ice nucleation sites have also been extensively studied at a molecular level. Nucleation sites active at high temperatures (above -5 degrees C) are probably composed of bacterial ice nucleation protein molecules that form functionally aligned aggregates. Models of ice nucleation proteins predict that they form a planar array of hydrogen binding groups that closely complement that of an ice crystal face. Moreover, interdigitation of these molecules may produce a large contiguous template for ice formation.

Bacteria↗
PubMed1994

Help from philosophy: responding to the animal rights challenge.

The chasm that C. P. Snow noted between the two cultures of science and the humanities may be part of an explanation for the success of the animal rights movement. Many philosophers, who represent the culture of the humanities, take an animal liberation position in the ethical debate about the use of animals in research. One who does not is Peter Carruthers. He presents a valuable critique of two important animal liberation ethicists, Tom Regan and Peter Singer, analyzing their thinking on the origins of ethical ideas and the source of ethical motivation. He identifies problems in their theories leading to conclusions that defy common sense about the value of human life. As an alternative, Carruthers introduces John Rawls' theory of contractualism. This theory provides a framework within which medical researchers and the public at large can defend the humane use of animals in research. His work promises to help bridge the gap between scientists and representatives of the humanities.

Animal Experimentation↗
PubMed1996

Late migration of an orbital implant causing orbital hemorrhage with sudden proptosis and diplopia.

A 31-year-old woman complained of sudden diplopia and proptosis associated with a headache. Approximately 10 years earlier, she had sustained a right orbital blowout fracture during a snow machine accident that was repaired using a Supramid implant. She presented with 4 mm of right-sided proptosis by Hertel exophthalmometry, with limitation of up and down gaze. She manifested a right gaze preference with a left head turn to achieve fusion. Visual acuity was 20/20 on both sides; however, there was 20% red desaturation and a subtle afferent pupillary defect on the right side. Goldmann visual fields were full and the retinal examination was normal. A computed tomography (CT) scan of the orbits with and without contrast demonstrated a large right posterior inferior orbital mass. Once the periorbita was breached during orbitotomy, a burgundy serosanguinous material emerged. Gram staining revealed red cells without organisms. The implant had not been fixed by wires or screws. Upon removal, the implant appeared oversized, encompassing the orbital floor, medial and lateral walls. Postoperatively, the proptosis, gaze preference with face turn, afferent pupillary defect, desaturation abnormality, and diplopia resolved.

Adult↗
PubMedDate not supplied

Strategic groups and outcomes in nursing facilities.

This article uses the Miles and Snow typology of strategies to examine nursing facilities' strategic responses to their changing environment and whether strategic responses are associated with facilities performance in quality outcomes. The author hypothesizes that prospector nursing facilities will have the highest quality outcomes, followed by defender, analyzer, and reactor facilities.

Catheterization↗
PubMed1996

Model testing using Chernobyl data: I. Wash-off of 90Sr and 137Cs from two experimental plots established in the vicinity of the Chernobyl reactor.

The "Wash-off" scenario is designed to test models concerned with the movement of trace contaminants from terrestrial sources to bodies of water, specifically the contamination of surface water by wash-off of radionuclides initially deposited onto soils. Particular emphasis is placed on chemical speciation and on the geochemical and geophysical processes affecting transfer of contaminants from soil to water. The scenario gives descriptions of two experimental plots near the Chernobyl power plant, one using heavy rain and one using snow melt, together with characteristics of the initial aerial deposition of the radionuclides and data on topography, soil type and characteristics, and time-varying precipitation. Predictions are requested for (1) the vertical distribution of concentrations of exchangeable and nonexchangeable forms of 137Cs and 90Sr in the soil of the experimental plots, (2) concentrations of 137Cs and 90Sr in runoff water from the experimental plots, and (3) total amounts of 137Cs and 90Sr removed by runoff from the experimental plots. Test data (field measurements) are available for all endpoints.

Cesium Radioisotopes↗
PubMed2002

Environmental gamma-ray dose rate in Aomori Prefecture, Japan.

Japan's first commercial nuclear fuel cycling facilities, including a spent nuclear fuel reprocessing plant, are now under construction in Rokkasho, Aomori Prefecture (prefecture--an area of administration similar to a county in the U.S.). The reprocessing plant is due to be completed by 2004. We surveyed indoor and outdoor environmental gamma-ray dose rates throughout Aomori Prefecture from 1992 to 1996 to get background data before operation of the plant. Glass dosimeters were used to measure cumulative gamma-ray dose rate. The outdoor gamma-ray dose rates were measured at 109 locations in the prefecture. The indoor gamma-ray dose rates were measured at 81 locations, which were generally in a dwelling near the location of an outdoor measurement. The contribution of radionuclides in the ground to the outdoor dose rate was estimated by using in-situ gamma-ray spectrometry with a germanium detector. The spectra were measured at 20 locations used for the glass dosimeter measurements. The outdoor gamma-ray dose rate was higher in the Tsugaru area (western part of the prefecture) than in the Nanbu area (eastern part). Means of the dose rate were 28, 31, and 25 nGy h(-1) for the whole prefecture and Tsugaru and Nanbu areas, respectively. The dose rates in winter were lower than those in the other seasons due to the shielding effect of snow on the ground. Mean contributions of uranium series, thorium series and 40K to the dose rates were 7.7, 8.2, and 9.3 nGy h(-1), respectively. The indoor dose rate was generally higher than the outdoor one, and the mean ratio of indoor to outdoor dose rates was 1.42. Means of indoor gamma-ray dose rate were 41, 37, and 43 nGy h(-1) for the whole prefecture and Tsugaru and Nanbu areas, respectively. The average effective dose rate to people in the prefecture was estimated to be 0.24 mSv y(-1).

Air Pollution, Indoor↗
PubMed1996

Spectrum of injuries from snowboarding.

OBJECTIVE: To examine and compare the types, frequency, and associated risk factors of injuries sustained in snowboarders with downhill skiers. DESIGN: Prospectively administered survey. MATERIALS AND METHODS: All snowboarders and skiers who presented to a rural hospital emergency department in California during one winter season were asked to answer a survey eliciting information regarding participants' demographics, previous experience, equipment use and circumstances surrounding their injury. MEASUREMENTS AND MAIN RESULTS: An overall response rate of 87.4% yielded examination of 355 injured snowboarders. Victims tended to be male (81%) with a mean age of 19.8. Snowboarders were more likely to injure the upper limb than skiers (58% vs. 32%, respectively, p < 0.001) but less likely to injure the lower extremities (16% vs. 35%, p < 0.001). Wrist injuries were most common. Nonorthopedic injuries were less common but potentially life threatening. The data also suggest that aerial maneuvers are associated with increased risk of injury to the head, face, spine, and abdomen and that collisions are associated with more severe injury. Snow conditions had no apparent effect on the type, location, or severity of injury and the reported use of alcohol and drugs was low (7%). It was estimated that snowboarders comprised 20 to 25% of participants on the slope but represented 45% of emergency department visits. CONCLUSIONS: There exists a wide spectrum of injuries from snowboarding, ranging from common extremity injuries to potentially life-threatening nonorthopedic trauma.

Adolescent↗
PubMed1994

Recent developments with human caliciviruses.

Caliciviruses (CVs) are human and animal pathogens. The best known human CVs are Norwalk virus (NV) and Snow Mountain agent. Recent molecular studies have confirmed that CVs are a unique taxonomic family. These molecular studies also have clarified relationships among previously poorly characterized human enteric viruses, led to new diagnostic tests and identified potential relationships between human and animal CVs. The purpose of this review was to describe these recent developments.

Animals↗
PubMed1995

Treatment of nevus Ota by liquid nitrogen cryotherapy.

Nevus Ota is a disfiguring facial dermal melanosis that is observed rarely in Caucasians but is common in Asians. Until recently, carbon dioxide snow cryotherapy had been used most frequently to treat this disorder, but the results were not always satisfactory and often left scarring after treatment. During the past 15 years, we have treated a total of 600 cases of dermal pigmentary facial disfiguration using CRYO-MINI, a liquid nitrogen cryogenic instrument with a removable disk-shaped copper tip. We have found this method to be simple and extremely effective in the treatment of nevus Ota and senile lentigines, and it is also useful for treatment of delayed nevus spilus and blue nevus. This report presents our techniques and experiences as well as the results achieved with four patients who have a deeply situated type of nevus Ota. Associated problems to be considered in future treatment are discussed also.

Adult↗
PubMed1998

Efficacy of the ruby laser in the treatment of Ota's nevus previously treated using other therapeutic modalities.

Ruby laser treatment, especially with a Q-switched laser, is remarkably effective for Ota's nevus, although a wide variety of other therapeutic modalities have had limited success. Consequently, laser treatment is now considered the treatment of choice. However, for Ota's nevus previously treated with dry ice cryotherapy (carbon dioxide snow), dermabrasion, free skin grafting, or other methods, therapy is still a challenge, even with the ruby laser. In this study, 14 patients with Ota's nevus previously treated using other modalities were treated using a Q-switched ruby laser. Eight patients previously underwent dry ice cryotherapy, three patients underwent free skin grafting, two patients underwent dermabrasion, and one patient received a cosmetic tattoo. The study group was composed of five male and nine female patients. The ages of the patients at the start of treatment ranged from 5 to 62 years. We concluded, based on the findings of this study, that Q-switched ruby laser therapy can provide favorable results even with lesions previously treated by other therapeutic modalities, provided that the treatment sessions are repeated more frequently and over a longer period of time than those used for untreated lesions and that they are combined with plastic surgical techniques such as scar resection or local flaps.

Adolescent↗
PubMed1995

The American Social Health Association celebrates 80 years of fighting sexually transmitted diseases.

The American Social Health Association (ASHA) can look back on 80 years of service as the only national nongovernmental organization devoted exclusively to prevention of sexually transmitted diseases (STDs). The valuable contributions made by physicians since the agency's founding in 1914 are noted and gratefully acknowledged. To commemorate its 80th anniversary, ASHA recently published a history that discusses the movements leading to ASHA's founding, the organization's work with the military during the World Wars, the changing face of STD control once penicillin became widely available in the 1940s, and the response to newly identified infections in recent decades. It also lists ASHA's founders, board presidents, executive directors, and recipients of the William Freeman Snow Award for outstanding contributions in the field of sexually transmitted diseases. The history was written by Kay Flaminio and David Klaassen of the ASHA Archive. This article summarizing ASHA's history was written especially for the Journal by Sam A. Nixon and Kay Flaminio. Nixon, a long-time member of the Southern Medical Association, recently retired as an associate network medical director of BlueCross BlueShield of Texas. He has maintained an interest in STD prevention and the work of the ASHA for many years, currently serving as the vice chair of ASHA's board of directors. Kay Flaminio is a member of the staff of ASHA.

Centers for Disease Control and Prevention, U.S.↗
PubMed1998

Deficiency of cytosolic arylamine N-acetylation in the domestic cat and wild felids caused by the presence of a single NAT1-like gene.

The purpose of this study was to determine the molecular basis for a relative deficiency in the cat of cytosolic arylamine N-acetyltransferase (NAT), an enzyme family that is important in the metabolism of xenobiotics and that normally consists of at least two related enzymes, NAT1 and NAT2. N-acetyltransferase in feline liver showed high affinity (mean Km = 2.1 microM) for p-aminobenzoic acid, an NAT1 selective substrate in humans and rabbits, but showed a very poor affinity (mean Km > 10 mM) for sulfamethazine, an NAT2 selective substrate in humans and rabbits. Immunoreactive N-acetyltransferase was detected in feline liver, bladder and colon using an NAT1-specific antipeptide antibody, but was not detected in any tissues using an NAT2-specific antibody. Southern blot analysis of genomic DNA demonstrated a single band in domestic cats using each of six restriction digests; single bands were also found on Southern blot analysis of six wild felids. The deduced amino acid sequence of the central portion of feline N-acetyltransferase, obtained by polymerase chain reaction amplification in both domestic cats and seven wild felids (lion, tiger, lynx, snow leopard, bobcat, Asian leopard cat and cheetah), contained three residues, Phe125, Arg127, and Tyr129, which determine NAT1-like substrate specificity in humans. These results support the conclusion that cytosolic arylamine N-acetylation activity is low in the cat because of the presence of a single N-acetyltransferase that has substrate specificity, immunogenicity and sequence characteristics similar to human NAT1, and that the unusual presence of only a single N-acetyltransferase gene appears to be a family wide trait shared by other felids.

Acetylation↗