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PubMed2006

Global sea-level rise is recognised, but flooding from anthropogenic land subsidence is ignored around northern Manila Bay, Philippines.

Land subsidence resulting from excessive extraction of groundwater is particularly acute in East Asian countries. Some Philippine government sectors have begun to recognise that the sea-level rise of one to three millimetres per year due to global warming is a cause of worsening floods around Manila Bay, but are oblivious to, or ignore, the principal reason: excessive groundwater extraction is lowering the land surface by several centimetres to more than a decimetre per year. Such ignorance allows the government to treat flooding as a lesser problem that can be mitigated through large infrastructural projects that are both ineffective and vulnerable to corruption. Money would be better spent on preventing the subsidence by reducing groundwater pumping and moderating population growth and land use, but these approaches are politically and psychologically unacceptable. Even if groundwater use is greatly reduced and enlightened land-use practices are initiated, natural deltaic subsidence and global sea-level rise will continue to aggravate flooding, although at substantially lower rates.

Disaster Planning↗

PubMed2006

Carnivore-livestock conflicts: effects of subsidized predator control and economic correlates on the sheep industry.

Despite the importance of carnivores in terrestrial ecosystems, many nations have implemented well-coordinated, state-funded initiatives to remove predators, largely because of conflicts with humans over livestock. Although these control efforts have been successful in terms of the number of carnivores removed, their effects on the viability of the industries they seek to protect are less understood. I assessed the efficacy of long-term efforts by the U.S. government to improve the viability of the sheep industry by reducing predation losses. I used regression analysis and hierarchical partitioning of a 60-year data set to explore associations among changes in sheep numbers and factors such as predator control effort, market prices, and production costs. In addition, I compared trends in the sheep industry in the western United States, where predator control is subsidized and coyotes (Canis latrans) are abundant, with trends in eastern states that lack federally subsidized predator control and that were (1) colonized by coyotes before 1950 or (2) colonized by coyotes between 1950 and 1990. Although control efforts were positively correlated with fluctuations in sheep numbers, production costs and market prices explained most of the model variation, with a combined independent contribution of 77%. Trends in sheep numbers in eastern and western states were highly correlated (r > or = 0.942) independent of the period during which they were colonized by coyotes, indicating either that control has been ineffective at reducing predation losses or that factors other than predation account for the declines in both regions. These results suggest that government-subsidized predator control has failed to prevent the decline in the sheep industry and alternative support mechanisms need to be developed if the goal is to increase sheep production and not simply to kill carnivores.

Animal Husbandry↗

PubMedDate not supplied

Femoral strain distribution and subsidence after physiological loading of a cementless canine femoral prosthesis: the effects of implant orientation, canal fill, and implant fit.

Twelve normal greyhound femora were divided into three groups. In group one, femoral stems were placed in neutral position with maximal fill. Group two had undersized femoral stems placed in neutral position. Group three had undersized femoral stems placed in varus position. Intact and implanted femora were loaded from 10 newtons (N) to 300 N in axial compression at a rate of 25 N/s for 10 replications. A strain gauge analysis showed that the strain distribution of all implanted femora were substantially different from intact femora, but femora with large implants placed in neutral position had the least amount of deviation from normal. An undersized stem in neutral position had significantly less compressive longitudinal strains along the proximomedial and proximocranial cortices. An undersized stem in varus position improved implant fit along the proximomedial and distolateral cortices, which resulted in increased tensile hoop strains. There were multiple significant correlations between the strain data and implantation variables (implant alignment, canal fill, and implant fit). Subsidence was significantly greater for the undersized implant in neutral position. There was not a difference in subsidence between the large neutral and varus groups. The most important variable that decreased subsidence was increased lateral implant fit (r = -0.86, P = .0003).

Animals↗

PubMedDate not supplied

Surface flow boundary conditions in modeling land subsidence due to fluid withdrawal.

Land subsidence due to subsurface fluid (water, gas, oil) withdrawal is often predicted by either finite element or finite difference numerical models based on coupled poroelastic theory, where the soil is represented as a semi-infinite medium bounded by the traction-free (ground) surface. One of the variables playing a most important role on the final outcome is the flow condition used on the traction-free boundary, which may be assumed as either permeable or impermeable. Although occasionally justified, the assumption of no-flow surface seems to be in general rather unrealistic. A permeable boundary where the fluid pressure is fixed to the external atmospheric pressure appears to be more appropriate. This paper addresses the response, in terms of land subsidence, obtained with a coupled poroelastic finite element model that simulates a distributed pumping from a horizontal aquifer confined between two relatively impervious layers, and takes either a permeable boundary surface, i.e., constant hydraulic potential, or an impermeable boundary, i.e., a zero Neumann flow condition. The analysis reveals that land subsidence is rather sensitive to the flow condition implemented on the traction-free boundary. In general, the no-flow condition leads to an overestimate of the predicted ground surface settlement, which could even be 1 order of magnitude larger than that obtained with the permeable boundary.

Atmospheric Pressure↗

PubMed2006

Accessing government subsidized specialist orthodontic services in Western Australia.

BACKGROUND: In Australia there is growing demand for dental services. This leads to more pressure on the oral health service providers, and in particular government subsidized dental care. Against this backdrop it is important that government dental services (rationed to health care cardholders) are provided equitably on a basis of need, not access. The primary hypothesis investigated in this study was that there would be an even distribution of patients referred for government subsidized orthodontic care across Western Australia when regionally adjusted for socio-economic status. METHODS: Data were obtained as a de-identified waiting list for orthodontic treatment at The University of Western Australia. The data included all patients on the orthodontic waiting list as at December 2003. RESULTS: Significant differences between ARIA categories were detected when all waiting list entries were distributed. However, the trend was towards more entries (adjusted for population) in highly accessible areas. It was found that people from relatively wealthy areas tended to be more likely to be on the waiting list than those from more disadvantaged regions. CONCLUSION: In summary, the results of this study indicate that there is an uneven distribution of demand for orthodontics waiting list positions across Western Australian postcode areas by remoteness (ARIA) and by socio-economic disadvantage (IRSD). The results suggest that demand for subsidized orthodontic care may be influenced by the general demand for treatment of that region and not on what would be expected to be an even need for treatment across all health care cardholders.

Adolescent↗

PubMed1980

Subsidence of the femoral prosthesis in total hip replacement in relation to the design of the stem.

A method is described of measuring radiological subsidence of a femoral prosthesis in relation to the femur after total hip arthroplasty. The method depends on measuring the distance from the tip of the femoral prosthesis to a fixed point in the bone. Subsidence after the use of a conventional design of femoral stem is compared with that after the use of a stem with a dorsal flange (Cobra). A significant reduction in the incidence and amount of subsidence was found when using the dorsal flange. There was also a notable absence of transverse fractures involving the cement near the tip of the stem, which occurred in 26 per cent of the cases using a conventional prosthesis.

Biomechanical Phenomena↗

PubMed1997

Acrylic cement creeps but does not allow much subsidence of femoral stems.

It has been suggested that the endurance of cemented femoral reconstructions in total hip arthroplasty is affected by the creep of acrylic cement, but it is not known to what extent cement creeps under loading conditions in vivo, or how this affects load transfer. We have simulated the long-term creep properties of acrylic cement in finite-element models of femoral stem constructs and analysed their effects. We investigated whether subsidence rates measured in vivo could be explained by creep of acrylic cement, and if polished, unbonded, stems accommodated creep better than bonded stems. Our findings showed that polished prostheses subsided only about 50 microm as a result of cement creep. The long-term prosthetic subsidence rates caused by creep of acrylic cement are therefore very small and do not explain the excessive migration rates which have sometimes been reported. Cement creep did, however, relax cement stresses and create a more favourable stress distribution at the interfaces. These trends were found around both the bonded and unbonded stems. Our results did not confirm that polished, unbonded, stems accommodated creep better than bonded stems in terms of cement and interface stress patterns.

Acrylic Resins↗

PubMed1997

Dyskinesias subside off all medication in a boy with autistic disorder and severe mental retardation.

A boy with autistic disorder and severe mental retardation developed severe dyskinesias, including objective akathisia (probable) and tics, a month after discontinuation of at least two years of treatment with drugs block dopamine receptors. These dyskinesias greatly subsided during a 17-wk. open-label nonblind clinical trial of clomipramine, and returned transiently when the parents abruptly discontinued clomipramine. However, the dyskinesias gradually subsided during two and a half years of follow-up with the boy being off all medication. A few stereotypies remain. We believe this suggests the hypothesis that movement disorders, such as withdrawal and tardive akathisia and tics, occurring in boys with autistic disorder treated with dopamine receptor-blocking drugs may subside months or years after discontinuation of the agents and that clomipramine may facilitate this process. We also hypothesize that some boys with autistic disorder and mental retardation exhibit fewer movement disorders, fewer psychiatric symptoms, and better over-all functioning after they have received no dopamine receptor-blocking drugs for several months, and this improvement continues years after the medication has ceased.

Akathisia, Drug-Induced↗

PubMed1992

Reducing the number of uninsured by subsidizing employment-based health insurance. Results from a pilot study.

OBJECTIVE: To evaluate whether employers who do not provide health insurance would offer such benefits after a 50% reduction in the price of health insurance. DESIGN: Using a survey of 530 firms at two sites in New York State, we estimate the number of firms that added insurance during 1988 as a percentage of firms that were eligible for the subsidy. We use this proportion as an estimate for the number of firms that would have added insurance in the absence of the subsidy program. We then estimate the number of firms adding insurance during the initial year of the program, 1989. SETTING: The subsidized health insurance pilot projects were available in Brooklyn and in the Albany-Plattsburgh-Poughkeepsie region of New York State. INTERVENTION: New York State subsidized the price of health insurance, reducing it by 50%. Eligible employers were responsible for paying the remaining portion of the premium. RESULTS: The subsidized health insurance products increased the number of small firms (under 20 employees) offering insurance by a small amount, approximately a 3.5 percentage point increase. When fully implemented and assuming all eligible employers were aware of the program, the subsidy would increase the proportion of firms offering insurance by 16.5 percentage points. We view this as an upper boundary. CONCLUSIONS: Increased program visibility and allowing the employee to share in the premium payment may increase the number of employers offering insurance. Even under ideal conditions, however, the results highlight the limitations of voluntary programs to increase the number of employers offering health insurance.

Health Benefit Plans, Employee↗

PubMed1988

The effects of the collar on total hip femoral component subsidence.

Twenty-four preserved autopsy femurs were used to evaluate the effect of the collar and tight distal fit on noncemented femoral component subsidence, micromotion, and load to failure. Ten collared implants (five with tight and five with loose distal fit) and 14 collarless implants (seven with tight and seven with loose distal fit) were inserted with press-fit technique. They were compressively loaded in an Instron machine (Instron, Canton, Massachusetts) at 25-kg increments with 20 cycles applied at each load level. Subsidence was significantly decreased, and load to failure increased by the collar. None of the parameters was significantly affected by tight fit of the cylindrical distal stem. Tightening of the collarless implant by subsidence could not be relied upon to achieve fixation, and may not be reliable in a clinical situation. Improved rigidity of fixation and increased strength achieved by seating on the collar are distinctive advantages for pain control and biologic fixation of noncemented femoral components.

Biomechanical Phenomena↗

PubMed1984

[Biocompatibility of implants with and without fluorohydrocarbon glow-discharge polymer coating. 3. Mathematical models of the subsiding processes of the tissue reaction].

The subsidence process of the tissue reaction was estimated by the thickness of the fibrous capsule as well as different histologic characteristics in dependence on the period after the implantation of 4 several implant materials. This subsidence process was fitted mathematically by an exponential function respectively a power function by means of the regression analysis. The power function described best the experimentally found curve. The correspondence, on principle, of the subsidence process of the fibrous capsula thickness on the one hand and the 9 histologic characteristics on the other hand could be proved. A standard valuation for subcutaneous tests is demanded which include the designation of the thickness of the fibrous capsula as well as characteristic cell type frequencies as histologic characteristics.

Animals↗

PubMed1994

Analysis of the bone surface area in resected tibia. Implications in tibial component subsidence and fixation.

Anterior subsidence of the tibial component is still a clinical complication requiring revision in total knee replacement. Using the scanning electron microscope, a quantitative 3-dimensional stereoscopic and digitizing study was conducted on the cortical and cancellous bone surface area from 10 resected human cadaveric tibia. The data demonstrated that the cortical bone surface area covered an average of 6% of the total tibial surface area, cancellous bone 18%, and bone marrow space 76%. By conducting anatomic regional analysis, the data showed significantly higher (p < or = 0.05) bone quantities in the posteromedial and medial regions as compared with the anterior and anterolateral regions. These data help to explain why tibial component subsidence occurs anteriorly in total knee replacement. The data also suggest that if long-term component subsidence and loosening is to be limited, either biologic cement or bone cement would be required to increase the surface attachment between the tibial component and resected cancellous bone.

Adult↗

PubMed1976

The effect of subsidized family planning services on reproductive behavior in the United States, 1969-1974.

This paper evaluates the impact of federally subsidized family planning programs in the United States, from 1969 to 1974, on the reproductive behavior of ever-married women, 15-44 years old. The study began with an experimental design and the random assigment of areas to treatment and control but was completed as a multivariate analysis, treating program input as an interval-scaled independent variable. Using "before" and "after" area sample surveys and patient service data from operating programs, the demographic impact of the program was estimated. The impact detected was nonsignificant; according to our analysis, overall use of physician-administered contraception was not affected by the subsidized programs. The only program-induced change of activity related to reproduction that we recorded was increased use of subsidized services in study areas with high program input and increased use of private physician services where program input was low. These findings need to be interpreted with the caution usually exercised in evaluating imperfect field experiments.

Adolescent↗

PubMed1993

Changes in the proteins coating monosodium urate crystals during active and subsiding inflammation. Immunogold studies of synovial fluid from patients with gout and of fluid obtained using the rat subcutaneous air pouch model.

OBJECTIVE: In this in vivo study, we investigated changes in the proteins that coat monosodium urate (MSU) crystals in human synovial fluid samples and rat air pouch fluid samples obtained sequentially during periods of active and resolving inflammation, in order to evaluate whether in vivo findings are consistent with hypotheses on roles of protein coating based on in vitro findings. METHODS: Crystals from patients with gout were isolated from joint fluids with acute inflammation, and subsequently from the same joints at the time inflammation was resolving. Crystals were also obtained using the rat subcutaneous air pouch model. Immunogold was used to label proteins coating MSU crystals, for light microscopy (LM) and transmission electron microscopy (TEM) studies. RESULTS: Dense immunogold-silver labeling for IgG was observed under LM on crystals from fluid with acute inflammation, whereas other proteins (apolipoproteins [Apo], fibronectin, fibrinogen, albumin) were not labeled significantly. Apo B became strongly positive on crystals as the inflammation subsided, whereas other proteins were only weakly positive and IgG became absent or weakly positive. Quantitative TEM evaluation confirmed the LM observations. CONCLUSION: This study provides the first in vivo evidence supporting the notion derived from previous in vitro studies that proteins coating MSU crystals change as inflammation evolves. Protein coatings may play an important role in the self-limited nature of gouty inflammation. IgG coating MSU crystals may enhance the inflammation. As the inflammation subsides, Apo B could displace the IgG by competitively coating sites on crystals and could contribute in part to the resolution of the acute gouty arthritis.

Aged↗

PubMed2003

Marine resources subsidize insular rodent populations in the Gulf of California, Mexico.

Inputs of energy and nutrients from one ecosystem may subsidize consumers in adjacent ones, with significant consequences for local communities and food webs. We used stable isotope and faecal pellet analysis to quantify use of ocean-derived resources by small mammals on islands in the Gulf of California, Mexico. Rodents were live-trapped on grids originating near shore and extending 125-200 m inland to evaluate the extent to which rodents transport marine nutrients inland, and to determine whether marine foods subsidize island populations, permitting higher densities than would be possible based on terrestrial resources alone. Both faeces and stable carbon and nitrogen isotopes revealed that omnivorous mice (Peromyscus maniculatus) consume ocean-derived prey, including littoral and supralittoral invertebrates, and that their diets differed markedly from those of granivorous rodents (Chaetodipus rudinoris). On a small, seabird roosting island, marine prey were important in the diet of mice regardless of their proximity to shore, underscoring the pervasive influence of the ocean on small islands with relatively large coastline area. On a large island, however, consumption of marine foods declined sharply > or =50 m from shore, which suggests that mice are poor conduits of inland movement of energy and nutrients from the sea. Marine resources seemed to act as subsidies for omnivorous rodents: more P. maniculatus were captured near shore than farther inland and there was an inverse relationship between island area and rodent abundance, suggesting that small islands with large amounts of marine inputs support the highest population densities. Patterns of local and island-wide abundance of P. maniculatus are likely the result of several interacting factors, including frustrated dispersal, competition with C. rudinoris, and the absence of predators. We speculate, however, that the availability of marine resources allows P. maniculatus to reach high densities and to persist on small islands in the Gulf despite low and unpredictable terrestrial productivity. Spatial trophic subsidies thus provide a possible mechanistic explanation for the widely reported inverse relationship between population density and island or habitat area.

Animals↗

PubMed2005

The impact of subsidized health insurance for the poor: evaluating the Colombian experience using propensity score matching.

This paper evaluates the impact of Colombia's subsidized health insurance program (SUBS) on medical care utilization. Colombia's SUBS program is a demand-side subsidy intended for low-income families, where the screening of beneficiaries takes place in decentralized locations across the country. Due to the self-selection problems associated with non-experimental data, we implement Propensity Score Matching (PSM) methods to measure the impact of this subsidy on medical care utilization. By combining unique household survey data with community and regional data, we are able to compute propensity scores in a way that is consistent with both the local government's decision to offer the subsidy, and with the individual's decision to accept the subsidy. Although the application of PSM using these rich datasets helps to achieve a balance between the treatment and control groups along observable dimensions, we also present instrumental variable estimates to control for the potential endogeneity of program participation. Using both methods, we find that Colombia's subsidized insurance program greatly increased medical care utilization among the country's poor and uninsured. This evidence supports the case for other Latin American countries implementing similar subsidy programs for health insurance for the poor.

Adolescent↗

PubMed1994

The choice of dental care sector by young adults before and after subsidization reform in Finland.

This work is a part of a project, which aims at studying the utilization of dental care by young adults and the effects of subsidization reform (SR) on it. SR was introduced in 1986 for the Finnish population born after 1960 and comprised a decrease of about 50% in the out-of-pocket price for dental care both in the public and private sector. The copayments are paid by the National Health Insurance in the private and municipalities through taxation in the public sector. In this work, the choice of dental care sector (private or public) before and after the reform and the effect of the reform on the choice are examined. The choice was measured by revealed preference; i.e. by actual choice in a period of two years before and after the reform. A random sample was drawn at the end of 1985 (before) and 1987 (after) from the population of 19-26/27 years of age in four towns, in which the conditions of supply of dental services differed essentially (n = 2250 at both occasions). The data were gathered by using a self-administered questionnaire. The method of analysis was discrete logit analysis and applied Chow-test. The changes in choices between 1985 and 1987 were counted by estimated model by using means of independent variables. The change in the choice of sector caused by the subsidization reform was marginal. The probability of choosing public sector increased 3%-points in the target group of the reform (19-25 aged), but the relative importance of different factors explaining the choice did not change. However, changes in the relative importance of explanatory factors took place in the first age group left outside the reform, but no clear picture was obtained about a possible change in the probability of choosing public sector in this group.

Adult↗

PubMed2005

Private and public cross-subsidization: financing Beijing's health-insurance reform.

In 1998, the Chinese government proposed a universal health-insurance program for urban employees. However, this reform has been advancing slowly, primarily due to an unpractical financing policy. We surveyed over 2000 families and evaluated the financial impacts of Beijing's reform on public and private enterprises. We found that most state-owned enterprises provided effective health insurance, whereas most private firms did not; overall, 33% of employees had little or no coverage. On average, employees of private firms were healthier and earned more compared to public firms. Because the premium was proportional to income, private firms would pay more for insurance than the predicted health-care expense of their employees. International firms subsidize the most, contributing more than 60% of their insurance premiums to the employees of the public sector. Such an aggressive cross-subsidization policy is difficult to be accepted by private firms.

Adult↗