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Atoll reefs are associated with subsiding regions. In the West Philippine Sea, the Kalayaan Island Group is an emergent feature of the region's atoll reefs. In this study, we established the long-term rate of subsidence in the Pag-asa Atoll Reefs by indicators of sea level positions on the seafloor and in Pag-asa Island. For submerged indicators of paleo-sea levels, a multibeam bathymetry with a 5-m resolution was used as the primary data source. Four pairs of submerged terraces and scarps, interpreted as former coral reef flats and reef fronts, respectively, were mapped. The terraces, PARa-d, from shallowest to deepest, occur at depth ranges of 7-10, 36-45, 82-90, and 115-120 m. The step-like morphology of the slopes off Pag-asa is likely due to the backstepping of reefs during the overall rise of sea level from the Last Glacial Maximum (LGM). Terraces PARa-d are interpreted as records of reef re-establishments during the stillstand periods following meltwater pulse event (MWP)-1C, MWP-1B, MWP-1A, and MWP-2B/2A. There is no clear morphological indicator of coral terraces that can be attributed to the LGM period. Variation in the widths and depths of the terraces between the leeward and windward sides of the island is also observed. Greater wave exposure appears favorable for coral reef terrace growth in Pag-asa, except for deeper terraces. The possible absence of the deepest terrace on the north side and an LGM terrace is attributed to possible thinner coral reef accretion due to the combination of cooler waters and possible swifter winds prior to 14 kyr. Correlation of the terrace depths and beach rock elevations as Pag-asa with the paleo-sea level of correlative stillstand events indicate long-term subsidence of 1.2 mm/yr between 15-12 kyr that declined to 0.3 mm/yr between 12 kyr to present. With sea level rise due to global warming and continuing subsidence, Pag-asa Island is threatened by coastal erosion, more frequent inundation, and groundwater salinization that needs to be addressed through proper adaptation practices. [ABSTRACT FROM AUTHOR]

This study investigated the effect of Physical Education 32 Fitness Exercises activities of the CMU first-year students during the Second Semester School Year 2018-2019. The focus of this study was on physical fitness status of the students using Physical Fitness Tests. The results revealed that the physical fitness level of the students has significantly improved, as this was shown in the health-related fitness test with an overall mean of 2.80 based on the conducted pre-test, while the result on the post-test manifested an overall mean of 3.06. The skill-related fitness pretest, obtained a mean score of 2.79 compared to post-test that had 3.33. This means that physical exercise and physical education-related activities helped improve the physical fitness condition of the respondents. Physical Education subject, particularly Physical Education 32, was effective in terms of health-related and skill-related parameters. This was after engaging in the various exercises' activity, found in the outcomes-based syllabus, there was a significant increase in the number of participants who were able to reach the high competence level of fitness. It also proved that the physical fitness test under the Physical Fitness battery of test could determine the physical fitness performance of the students. [ABSTRACT FROM AUTHOR]

Young adult (YA) cancer survivors often experience social isolation. Mobile apps facilitate peer-to-peer connections, yet little is known about their use. YA survivors (N = 181) were surveyed about a peer-to-peer cancer support app. Among those with it downloaded, 36% reported daily/weekly use. One-to-one messaging and group chat features were easy-to-use and useful, but facilitation of social presence was variable. Within group chats, 55% participated in discussions; 45% observed conversations without contributing. The app was helpful for convenient access to peer support (84%), particularly when offline social networks were inadequate (83%); some (16–25%) reported nervousness initiating connections. Qualitative feedback identified facilitators and barriers to adoption and sustained engagement. Recommendations centered on improving design and logistical factors and facilitating in-app connections. App-based peer support is promising for addressing social isolation among YA survivors. Future research should examine theory-based communication and design features to encourage meaningful engagement and longitudinal effects on psychosocial outcomes. [ABSTRACT FROM AUTHOR]

This is the first report of an aortic sinus aneurysm with a communication to the main pulmonary artery, resulting in left‐to‐right shunting, diagnosed in vivo in a dog. There was also a second left‐to‐right shunt through a patent ductus arteriosus. Computed tomography (CT) angiography was used to confirm both congenital anomalies and assess the relative contributions of the two left‐to‐right shunts to left‐sided volume overload. [ABSTRACT FROM AUTHOR]

Background: Malaria poses a major health risk for children under 5 in low resource settings. Building healthy practices for malaria management can prevent malaria-related deaths in children. Aim: The purpose of this study was to describe mothers' practices associated with malaria management in children under 5 in a suburban community in south-west Nigeria. Methodology: A community-based descriptive study was conducted among 160 mothers of children under 5 using a multistage sampling technique. Data were collected using a semi-structured, interviewer-administered questionnaire. Results: The majority (96.3%) of mothers had good knowledge of the causes and management of malaria; however, most (83.1%) did not adopt healthy practices in the management of malaria in children under 5. The majority (88.8%) of the mothers cited long waiting times to get treatment in health facilities as a major factor against uptake of hospital treatment for malaria. The use of antimalarial combination therapy for treatment of malaria was low among mothers (28.8%). Conclusions: Mothers' did not adopt healthy practices in malaria management for children under 5. It is essential to intensify efforts on health education programmes that can build mothers' capacity for healthy practices for malaria management. [ABSTRACT FROM AUTHOR]

In 2008, the CDC published guidelines recommending screening of all persons undergoing treatment with rituximab to identify persons at risk of hepatitis B virus (HBV) reactivation. We evaluated implementation of this recommendation in veterans, who are at increased risk of HBV, and determined characteristics of those screened. We also evaluated a control setting, rates of hepatitis C virus (HCV) screening among the same rituximab-treated patients. There are no guidelines that recommend HCV screening prior to initiation of rituximab. Medical records of patients receiving rituximab between January 2006 and December 2012 were reviewed according to two time periods: 2006-2008 (period 1, pre-guidelines) and 2009-2012 (period 2, post-guidelines). Patient demographics, concomitant chemotherapy regimen (protocol, dose, duration), treatment indication, risk factors for hepatitis infection (substance abuse, homelessness, human immunodeficiency virus (HIV)), and HBV/HCV screening status were documented. During the study period, 102 patients were treated with rituximab (49 in period 1 and 53 in period 2). During periods 1 and 2, 22 and 32 % of rituximab-treated patients were screened for HBV, respectively (p = 0.375). Treatment during 2009 was the only significant predictor of HBV screening in the adjusted model (p = 0.01). For HCV during periods 1 and 2, 22 and 21 % of patients were screened, respectively (p = 1.00). There were no significant predictors of HCV screening. Rates of screening for HBV among rituximab-treated patients were low, both before and after dissemination of guidelines recommending universal HBV screening of rituximab-treated patients. [ABSTRACT FROM AUTHOR]

Reports on the frequency dependent conductivity of the modified Huesler alloy UNiSn in the antiferromagnetic state and in the presence of a magnetic field. UNiSn as a paramagnetic; Magneto-optical measurements.

Earlier published rheological data of methyl methacrylate (MMA) heated and isothermally polymerized at temperatures between 50 and 80°C have been reanalyzed using three semiempirical models of viscosity advancement including a modified Boltzmann sigmoidal model, a microgel model for cure, and a first-order isothermal kinetic model. These alternative models possessed few fitting parameters and could be used without requiring more experiments to be run. For each dataset as a function of temperature, the analysis resolved time constants associated with both the induction time for polymerization and the rate of viscosity rise, which were inversely related to the polymerization temperature. We found the sigmoidal model the most robust to accommodate nonlinearities in viscosity advancement with radical polymerization of MMA. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Because many types of living cells are sensitive to applied strain, different in vitro models have been designed to elucidate the cellular and subcellular processes that respond to mechanical deformation at both the cell and tissue level. Our focus was to improve upon an already established strain system to make it capable of independently monitoring the deflection and applied pressure delivered to specific wells of a commercially available, deformable multiwell culture plate. To accomplish this, we devised a custom frame that was capable of mounting deformable 6 or 24 well plates, a pressurization system that could load wells within the plates, and a camera-based imaging system which was capable of capturing strain responses at a sufficiently high frame rate. The system used a user defined program constructed in Labview® to trigger plate pressurization while simultaneously allowing the deflection of the silicone elastomeric plate bottoms to be imaged in near real time. With this system, up to six wells could be pulsed simultaneously using compressed air or nitrogen. Digital image capture allowed near-real time monitoring of applied strain, strain rate, and the cell loading profiles. Although our ultimate goal is to determine how different strain rates applied to neurons modulates their intrinsic biochemical cascades, the same platform technology could be readily applied to other systems. Combining commercially available, deformable multiwell plates with a simple instrument having the monitoring capabilities described here should permit near real time calculations of stretch-induced membrane strain in multiple wells in real time for a wide variety of applications, including high throughput drug screening. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the epidemiology and disease process of streptococcal infection in dogs. The study cultured Streptococcus species from the skin and intestine of 393 dogs. Streptococcal organisms were isolated from 499 cases of the 2,432 samples cultured, and Streptococcus species were identified in 17 dogs. The clinical manifestations and pathology of Streptococcal infection in dogs are also described.

The article presents a study on various models for a comparative system analysis to determine which accurately represent viscosity. Data on polyurethane network polymerization at three temperatures are reanalyzed using a sigmoidal model and compared with a power law model for interpreting gel points. Gel times are similar between the power and sigmoidal models experimental dynamic viscosity data. The power law model requires interpretation of the junction region while the sigmoidal requires threshold viscosity.

The article presents a study which reanalyzed curing profiles of epoxy resins combined with an anhydride curing agent and crosslinked with a modified sigmoidal model to describe the dynamic viscosity accompanying resin curing. Information on kinetic factors yielded by the sigmoidal analysis is offered. The induction time identified by the log-sigmoidal model correlated closely with the gelation time identified with a modified-Williams-Landel-Ferry (WLF)-based model by M. Ivankovic et al.

Establishing trees in pastures can have production and conservation benefits, but is complicated by the presence of livestock. The need to protect seedlings from livestock increases tree establishment costs, which in turn, can deter landowners from planting trees. Living fences are a ubiquitous feature of pasture landscapes in the tropics that could help protect newly planted trees by preventing livestock trampling and browsing. This study quantified the effectiveness of a living fence in protecting tree seedlings during the first 2 years after planting. The four native tree species evaluated were: Cedrela odorata L., Pachira quinata (Jacq.) W.S. Alverson, Samanea saman (Jacq.) Merr., and Tabebuia rosea (Bertol.) A. DC. Results show that the living fence provided protection from livestock except in cases where tree species were highly palatable as forage (i.e. P. quinata). Trees planted into the living fence generally had greater survival (62 vs. 28%), relative growth (10.3 times initial height vs. 5.8 times initial height), and final height (191 cm vs. 108 cm) compared to those planted in open pasture after 2 years. However, survival and growth of trees planted into the fence remained lower than that observed at a nearby plantation with no livestock, regular weeding and no living fences. This study indicates that use of living fences as a protective barrier could be an effective low-cost approach for establishing trees in tropical pasture landscapes. [ABSTRACT FROM AUTHOR]

The conservation of crop genetic resources is an international priority and requires the continued collection and characterization of farmer varieties. We collected and characterized maize and upland rice populations cropped by farmers in Panama's Azuero region. The objective of our study was to evaluate the crop genetic diversity of farmer varieties of maize and upland rice grown by poor farmers in Panama. We found that: (1) farmers' naming practices only partially corresponded to genetic relationships and were the strongest for rice populations; (2) farmers' classification of populations as 'modern' or 'traditional' was reflected in phenotypic differences; (3) Panamanian maize populations were molecularly distinct from populations collected elsewhere in Latin America; and (4) heterogeneous rice populations were common and heterogeneity was often due to admixture of recognized farmer varieties. Our results indicate that poor farmers in Panama continue to farm 'traditional' varieties that harbour genetic diversity of interest. There has, however, been substantial adoption of 'modern' varieties. [ABSTRACT FROM AUTHOR]

A 34-year-old woman presented with acute and progressive pain in the upper abdomen with worsening nausea, vomiting and diarrhoea. Her pain was described as severe, sharp and stabbing, with radiation to her chest and back. The patient’s amylase and lipase levels were only mildly elevated. However, triglyceride levels (10 039 mg/dL) were markedly elevated upon presentation and no other causes of acute pancreatitis (e.g. obstruction, alcohol and medication) were identified. The patient was treated with opioids to control her pain and gemfibrozil was initiated to reduce her triglycerides. In addition, the patient received enoxaparin for deep vein thrombosis prevention and insulin for hyperglycaemia which also have been shown to decrease elevated triglycerides. The patient subsequently required antibiotic therapy with piperacillin–tazobactam after developing fever and an elevated white blood cell count. We review the role of adjunctive therapy with heparin and insulin in a patient with recurrent pancreatitis probably because of hypertriglyceridaemia and medication non-compliance. [ABSTRACT FROM AUTHOR]

This work investigates the settling response of bi-disperse silicone oil-based magnetorheological fluids with varying solids loading (content) of Fe magnetic particles at three ratios of nanoparticles to micron size particles. The solid loading (content) of Fe magnetic particles in silicone oil was 50 or 60% by weight with nanoparticle fractions of 0, 10, or 15% by weight of the total solids loading. Sedimentation experiments are conducted using Z-axis translating laser light scattering at ambient temperature. Sedimentation velocities are determined from clear layer separation and functional particulate transport by creeping flow. Settling rates of 1-3 mm/s have been observed in the dispersions without nanoparticles. Viscosity testing shows lower yield stress with nanoparticle inclusion and the typical rise in shear stress with increasing shear rate and applied magnetic field using both the linear Bingham and the non-linear Hershel-Bulkley models. Adding nanoparticles also reduced sedimentation velocity by roughly two orders of magnitude from those without nanoparticles. The nanoparticles act as plugs or otherwise interact in forming soft gel particulates leading to a denser sedimentation front yielding fewer percolation holes through which the fluid can permeate. Either way, the addition of nanoparticles leads to a more effective stabilization mechanism for the dispersion. [ABSTRACT FROM AUTHOR]

Protein conformational changes are often induced when bound to surfaces and can modulate colloidal stability of protein coated particles in dispersion. We evaluated bovine serum albumin (BSA) adsorbed onto polystyrene particles at room temperature. A z-axis translating laser light scattering device (ZATLLS) measured the sedimentation velocity of protein-coated particles tracking aggregation characteristics compared with non-coated ones. Sedimentation velocities of particles moving in the dispersion, and the resulting viscosity and density of the residual solution following sedimentation determined aggregate size in the dispersion using Stoke's law. Our experiments objectively show that albumin-coated polystyrene forms aggregates. Interestingly, coating particles with protein slows the sedimentation velocity which should correspond to a more dispersed system, but it leads to higher aggregate sizes due to the larger influence of proteins in solution raising solution viscosity. Protein-bound particles were observed to fall out of solution in a more controlled and steady manner compared with uncoated particles. [ABSTRACT FROM AUTHOR]

The article presents a study which analyzed the photopolymerizable urethane dimethacrylate resins with different diluent content and light fluence. It mentioned the use of an exponential model to examine the initial rise in viscosity. It noted that analytical approach taken could help in developing more sophisticated models that consider simultaneous flow and cure advancement in other thermosets.

A case of successful laser extraction of a defibrillator lead with baffle stenting in a 15-year-old boy with dextrocardia, L-transposition, ventricular septal defect, and pulmonic stenosis status-post Senning/Rastelli repair is presented. Six-month follow-up revealed a significant increase in exercise tolerance and maximum oxygen consumption (VO(2)max). [ABSTRACT FROM AUTHOR]

Health providers are challenged to find efficacious ways to provide health education to a population with diverse levels of health literacy. This project sought to test the effectiveness of a website (Diabetes and You) about Type II diabetes designed for non-diabetics with low health literacy. Research participants were observed as they viewed the Diabetes and You website, tested for diabetes knowledge before and after viewing the website, checked for functional health literacy, and interviewed to discover their perceptions of the website. Results indicate that users were engaged and interested in the website and particularly preferred the interactive risk assessment page. Users demonstrated an increase in knowledge about diabetes and its risks after viewing the website. Further research into the most effective ways of delivering health information online to this key target population is necessary to minimize the role of health literacy in limiting these individuals' acquisition and understanding of health information. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the extraction of model parameters associated with cure advancement to analyze the dynamic chemorheology of curing resins. Datasets from other published manuscripts on reactive resin curing were extracted by the authors and they have observed exponential growth in viscosity with the reactive systems. It was found that the dynamic viscocity rise in the resins advances with a similar exponential rise.

Conventional magnetorheological (M R) fluids are suspensions of micron-sized particles in a hydraulic or silicone oil carrier fluid. Recently, research has been conducted on the advantages of using bidisperse fluids, which are mixtures of two different powder sizes in the MR suspension. The MR fluids investigated here use a mixture of conventional micron-sized particles and nanometer-sized particles. The settling rate of such bidisperse fluids using nanometer-sized particles is reduced because the nanoparticles fill pores created between the larger particles, thereby reducing fluid transport during creeping flow. This reduction in the settling rate comes at a cost of a reduction in the maximum yield stress that can be manifested by such an MR fluid at its saturation magnetization. There is a measurable and predictable variation in rheological properties as the weight percent (wt%) of the nanometer-sized particles is increased relative to the weight percent (wt%) of micron-sized particles, while maintaining a constant solids loading in the MR fluid samples. All bidisperse fluids tested in this study have a solids loading of 60wt% of iron (Fe) particles. This study investigates the effect of increasing the wt% of 30 μnm (nominal) Fe particles relative on 30μm (nominal) Fe particles on rheological characteristics, such as yield stress and postyield viscosity. The goal of this study is to find an optimal composition of the bidisperse fluid that provides the best combination of high yield stress and low settling rate based on empirical measurements. The applicability of the Bingham-plastic rheological model to the measured flow curves of these MR fluids is also presented. [ABSTRACT FROM AUTHOR]

Telemedicine research addressing user satisfaction abounds in academic literature. Results from patient satisfaction studies indicate exceptionally high levels of perceived satisfaction, often above the rates of expected satisfaction for traditional forms of health delivery. Results from provider satisfaction studies are also generally quite positive; however, data from providers point to higher concerns with delivery barriers and challenges. Even though data from patient and provider satisfaction research suggests overwhelming optimism for this delivery modality, this paper urges cautious embracement of these results for several reasons. First, many of the studies exhibit serious methodological weaknesses related to design and data collection instruments. In addition, the construct of satisfaction is largely undefined and is not clear. Even recognizing these caveats, the results of the study do offer some evidence that patient satisfaction will not impede the deployment of telemedicine, but provider satisfaction merits additional study. [ABSTRACT FROM AUTHOR]

We analyze the initiation and propagation of adiabatic shear bands in a tungsten heavy alloy by modeling each constituent as a heat-conducting, microporous, isotropic, elastothermoviscoplastic material. The two constituents are assumed to be perfectly bonded to each other so that the temperature, heat flux, displacements, and surface tractions are continuous across an interface between a tungsten particulate and the nickel-iron matrix. Three different modes of deformation, namely plane strain tension/compression, plane strain shear, and axisymmetric tension/compression are analyzed. No other defects are introduced. It is found that contours of the rate of temperature rise and/or velocity and/or the specific energy dissipation rate rather than those of effective plastic strain delineate the shear banded regions. For the same volume fraction of particulates smaller diameter particulates enhance the formation of adiabatic shear bands. The time of initiation of an adiabatic shear band also depends upon the particulate arrangement. [ABSTRACT FROM AUTHOR]

The preparation of ground low-density poly(ethylene) (LDPE), high-density poly(ethylene) (HDPE), and poly(ethylene terephthalate) (PET) materials suitable for use by inverse gas chromatography (IGC) experiments is described. Materials prepared showed a smaller and more uniform particle size, 83–86 µm (200 mesh), than commercially available Chromosorb® W solid chromatography support. In addition, the BET surface area of polymeric materials, 0.367–0.559 m2/cm3, was much greater than the surface area of 150- to 212-µm-diameter glass beads. The use of polymeric materials with uniform particle sizes and defined surface areas have several advantages over polymer coated Chromosorb® W and glass beads in IGC experiments. [ABSTRACT FROM AUTHOR]

Sedimentation is a limiting factor for the shelf life of filled paints and adhesive resins, and requires consideration when optimizing a resin's formulation for an end application. Static settling experiments have been performed using a bis-GMA-based photocurable resin system by varying some characteristics of the filler particles (size and composition) and of the resin (viscosity and composition). The recorded batch settling curves, mudline height vs. time, displayed the standard sedimentation shape. In particular, the mudline movement rate was constant in the initial period of sedimentation. The variations of this constant mudline velocity as a function of the settling conditions has been compared to sedimentation model predictions. A close correspondence has been obtained between the data and a model describing the sedimentation behavior of non-aggregated rigid spheres at high concentration in the Stokes regime. In particular, the constant mudline velocity is proportional to the square of the particle diameter. This result can be used as a way to limit the settling phenomenon in filled resin systems, by choosing a particle diameter as small as possible. As a validation of this result, no visually observable settling was seen in 50%-filled resin systems for a period more than 4 months at room temperature using 5.1-μm poly(methyl methacrylate-co-ethylene glycol dimethacrylate) particles as filler. [ABSTRACT FROM AUTHOR]

A user friendly, Labview™ controlled, prototype settling device has been designed and built that incorporates a laser light source and detector fixtured to a z-axis translating stage. The Labview™ data interface drives the unit and captures data in the form of scattered intensity as a function of z-axis location. We present some examples of sample output from low- and high-density particles settling in epoxy fluids of various viscosities. This device maps all of the expected settling regimes and, more importantly, valuable scattering information about partial settling is found in instances without a discrete mud line. The effect of resin viscosity on settling has been measured and corresponds well to model predictions. Measurement of settling data in the compression regime was also achievable, validating descriptive models. [ABSTRACT FROM AUTHOR]

Although individuals with poor food security might be expected to have reduced food intake, and thus reduced body fat and less likelihood of being overweight, these associations have not been adequately studied. The purpose of the current study was to examine the relationship between food insecurity and overweight as measured by body mass index (BMI) using data from the nationally representative 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII). Overweight was defined as BMI >27.3 kg/m(2) for women and 27.8 kg/m(2) for men. Food insecurity was related to overweight status for women (n = 4509, P < 0.0001), but not for men (n = 4970, P = 0.44). Excluding the 11 severely insecure women, the prevalence of overweight among women increased as food insecurity increased, from 34% for those who were food secure (n = 3447), to 41% for those who were mildly food insecure (n = 966) and to 52% for those who were moderately food insecure (n = 86). Food insecurity remained a significant predictor of overweight status, after adjustment for potentially confounding demographic and lifestyle variables (P < 0.01). In a logistic regression analysis, mildly insecure women were 30% more likely to be overweight than those who were food secure [odds ratio (OR) 1.3, P = 0.005]. Thus, food insecurity had an unexpected and paradoxical association with overweight status among women with a higher prevalence of overweight among the food insecure, and a resulting potential for increased incidence of obesity-related chronic diseases. Given that the rates of both overweight and food insecurity are on the rise, this research area warrants further investigation. [ABSTRACT FROM AUTHOR]

Large-scale experiments on medflies that were subjected to sterilizing doses of ionizing radiation (plus intact controls) and maintained on either sugar-only or full, protein-enriched diets revealed that, whereas the mortality trajectories of both intact and irradiated male cohorts maintained on both diets are similar, the mortality patterns of females are highly variable. Mean mortality rates at 35 days in male cohorts ranged from 0.2 to 0.3 but in female cohorts ranged from 0.09 to 0.35, depending on treatment. The study reports three main influences: (a) qualitative differences exist in the sex-mortality response of medflies subjected to dietary manipulations and irradiation; (b) the female mortality response is linked to increased vulnerability due to the nutritional demands of reproduction; and (c) female sensitivity to environmental changes underlies the dynamics of the sex-mortality differential. [ABSTRACT FROM AUTHOR]

The dielectric properties of latex water-cast and conventional solvent-cast epoxy neat resin systems were investigated under three formation conditions: solvent-based as-made, water-based as-made, and water-based following a boiling fluid extraction procedure to remove residual surfactant. Samples from each of these three groups were cast, cured, and exposed to controlled humidities in an environmental chamber at room temperature and elevated temperature, a steam bath at various temperatures, and soaked in boiling water. Composite laminates, press fabricated using solvent and latex-based epoxy impregnated glass cloth, were subjected to similar environmental exposure. The microwave frequency dielectric properties of these materials, after each environmental exposure, were measured at 9.4 GHz. These dielectric measurements revealed that under identical exposure conditions, water-borne epoxy systems absorbed more water than solvent-based systems and also allowed more free water into the samples. Extraction of water and soluble components in the resin had no effect on the dielectric properties of the water-borne samples. The presence of high quantities of free water at moisture fractions beyond 4.0 wt %, suggests that the differences between the dielectric properties of solvent and water-borne epoxy systems are due to void morphology, which was confirmed by optical and electron microscopy. ©1999Kluwer Academic Publishers [ABSTRACT FROM AUTHOR]

Adhesion experiments were performed using both morphological and surface chemical modifications to identify whether one is dominant in controlling copper–epoxy adhesion and durability. Surface preparation procedures included sanding and etching copper surfaces which were thermally oxidized and a surface plating treatment that formed oxidized nodules on the copper surface. Further surface chemical modification used benzotriazole primary and chromium ion implantation on copper oxide. All prepared surfaces were laminated to an epoxy–glass resin cloth and the interfaces were aged in an air oven at 150°C. Adhesion with ageing time was measured by a floating roller peeler assembly attached to a mechanical load frame. Interfaces formed when copper was oxidized in air had significantly lower peel strength than interfaces prepared by the plating treatment. Furthermore, peel adhesion was significantly reduced by elevated temperature conditioning. Adhesion degradation kinetics were applied to the transitional peel adhesion data and kinetic parameters associated with degradation at 150°C were calculated. The results suggest that peel failure for the thermally oxidized samples occurs within the oxide layer, and that surface treatments on the oxide layer are not effective in altering adhesion. The peel adhesion of the electroplated surfaces was affected by the surface chemistry. No difference was observed in the fracture surface as a function of chemistry or ageing time. © 1997 Chapman & Hall [ABSTRACT FROM AUTHOR]