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The photooxidative stability of an aromatic segmented poly(urethane-urea) (PUU) elastomer, stabilised with a range of carbon black fillers, was assessed after very low UVA doses as a means to identify components that are highly susceptible to UV degradation, and suggest better design of such materials. Fourier-transform infrared (FTIR) analysis indicated rapid degradation of the urea bonds in the hard segments, followed by chain scission and photo-Fries reaction of the urethane linkages. In the soft segments, the oxidation of the original ether groups resulted in the formation of large amounts of ester groups, while some crosslinking of the ether groups was also evident. Carbon black provided moderate protection against degradation, with the smallest-sized particles being the most effective. Protection was evidenced by reduced surface cracking as well as an increased resistance to chemical changes in both the soft segments and hard segments. Even so, significant degradation was still evident at low UV doses suggesting that further stabilisation is required to increase the UV durability of these elastomers and improve their long-term performance.\ud \ud

The service lifetime of polymer films is controlled by the chemical reactions leading to chain scission and the mediating environmental factors. For application as agricultural cropping film, controlled accelerated degradation is required. For a photo-sensitive linear low density polyethylene (LLDPE) + 1% nano-titania (as the anatase/rutile mixed phase P25), the environmental factors are not only UV dose and temperature but also soil parameters such as moisture and organic material content. This provides a challenge in predicting the useful lifetime from laboratory accelerated ageing studies. To enhance degradation when the (LLDPE + 1% P25) is buried, UV-C pre-irradiation has been shown to accelerate strength loss but the rate of embrittlement is not sufficient for the application as crop propagation film. Biodegradable poly(butylene adipate-co-terephthalate) or PBAT has a higher rate of degradation when buried outdoors in soil than when buried under laboratory conditions: The elongation at break fell from 900% to 70% in one month in the field while similar changes required 6 months in the laboratory. The small changes in M n ¯ for embrittlement in the field suggests that the loss of mechanical properties was not linked to bulk property changes but rather to surface morphology (cracks and holes) as seen by SEM. This suggests that even in thin films, enzyme-mediated hydrolysis of PBAT is surface controlled. DNA analysis of the soil around the buried films after 35 days ageing outdoors showed fungi play a more dominant role in PBAT biodegradation compared to bacteria. UV degradation of PBAT film is controlled by the photochemistry of the terephthalate moiety in the polymer and the development of fluorescence is a useful indicator of the extent of photo-degradation.

The determination of the safe working life of polymer materials is important for their successful use in engineering, medicine and consumer-goods applications. An understanding of the physical and chemical changes to the structure of widely-used polymers such as the polyolefins, when exposed to aggressive environments, has provided a framework for controlling their ultimate service lifetime by either stabilising the polymer or chemically accelerating the degradation reactions. The recent focus on biodegradable polymers as replacements for more bio-inert materials such as the polyolefins in areas as diverse as packaging and as scaffolds for tissue engineering has highlighted the need for a review of the approaches to being able to predict the lifetime of these materials. In many studies the focus has not been on the embrittlement and fracture of the material (as it would be for a polyolefin) but rather the products of degradation, their toxicity and ultimate fate when in the environment, which may be the human body. These differences are primarily due to time-scale. Different approaches to the problem have arisen in biomedicine, such as the kinetic control of drug delivery by the bio-erosion of polymers, but the similarities in mechanism provide real prospects for the prediction of the safe service lifetime of a biodegradable polymer as a structural material. Common mechanistic themes that emerge include the diffusion-controlled process of water sorption and conditions for surface versus bulk degradation, the role of hydrolysis versus oxidative degradation in controlling the rate of polymer chain scission and strength loss and the specificity of enzyme-mediated reactions.

A range of profluorescent nitroxides (PFNs) were tested as probes to monitor photo-induced radical-mediated damage in polymer materials. The most stable and sensitive probe of the PFNs tested was an alkyne-linked perylenediimide PFN, 6b, with napthalimide and 9,10-bis(phenylethnyl)anthranene-based versions giving lower stability and sensitivity. Results from photo-ageing of poly(1-trimethylsilyl)-1-propyne (PTMSP) and the ethylene norbornene copolymer (TOPAS®) films doped with PFN probes demonstrated that sensors employing these support materials deliver significantly enhanced sensitivity compared to traditional techniques used to monitor photo-oxidative degradation of polymers, such as infrared spectroscopy. This enhanced sensitivity for detecting polymer damage improved methods for the determination of the serviceable application lifetime of polymers.

Background Many CpGs become hyper or hypo-methylated with age. Multiple methods have been developed by Horvath et al. to estimate DNA methylation (DNAm) age including Pan-tissue, Skin & Blood, PhenoAge, and GrimAge. Pan-tissue and Skin & Blood try to estimate chronological age in the normal population whereas PhenoAge and GrimAge use surrogate markers associated with mortality to estimate biological age and its departure from chronological age. Here, we applied Horvath’s four methods to calculate and compare DNAm age in 499 subjects with type 1 diabetes (T1D) from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study using DNAm data measured by Illumina EPIC array in the whole blood. Association of the four DNAm ages with development of diabetic complications including cardiovascular diseases (CVD), nephropathy, retinopathy, and neuropathy, and their risk factors were investigated. Results Pan-tissue and GrimAge were higher whereas Skin & Blood and PhenoAge were lower than chronological age (p < 0.0001). DNAm age was not associated with the risk of CVD or retinopathy over 18–20 years after DNAm measurement. However, higher PhenoAge (β = 0.023, p = 0.007) and GrimAge (β = 0.029, p = 0.002) were associated with higher albumin excretion rate (AER), an indicator of diabetic renal disease, measured over time. GrimAge was also associated with development of both diabetic peripheral neuropathy (OR = 1.07, p = 9.24E−3) and cardiovascular autonomic neuropathy (OR = 1.06, p = 0.011). Both HbA1c (β = 0.38, p = 0.026) and T1D duration (β = 0.01, p = 0.043) were associated with higher PhenoAge. Employment (β = − 1.99, p = 0.045) and leisure time (β = − 0.81, p = 0.022) physical activity were associated with lower Pan-tissue and Skin & Blood, respectively. BMI (β = 0.09, p = 0.048) and current smoking (β = 7.13, p = 9.03E−50) were positively associated with Skin & Blood and GrimAge, respectively. Blood pressure, lipid levels, pulse rate, and alcohol consumption were not associated with DNAm age regardless of the method used. Conclusions Various methods of measuring DNAm age are sub-optimal in detecting people at higher risk of developing diabetic complications although some work better than the others.

The impact of microplastic pollution on terrestrial biota is an emerging research area, and this is particularly so for soil biota. In this study, we addressed this knowledge gap by examining the impact of aged low-density polyethylene (LDPE) and polyester fibres (i.e. polyethylene terephthalate, PET) on a forest microbiome composition and activity. We also measured the corresponding physicochemical changes in the soil. We observed that bacteria community composition diverged in PET and LDPE treated soils from that of the control by day 42. These changes occurred at 0.2% and 0.4% (w/w) of PET and at 3% LDPE. Additionally, soil respiration was 8-fold higher in soil that received 3% LDPE compared to other treatments and control. There were no clear patterns linking these biological changes to physicochemical changes measured. Taken together, we concluded that microplastics aging in the environment may have evolutionary consequences for forest soil microbiome and there is immediate implication for climate change if the observed increase in soil respiration is reproducible in multiple ecosystems.

The following paper discusses the manner in which the liberty of the local church should be qualified if a local gathering is to be recognized both as validly a church and validly a baptist church. With these qualifications in mind the paper then revisits the Baptist Union of Great Britain's Declaration of Principle, noting the commitment to a congregational church order together with a commitment to credo-baptism as the key identifying markers. Finally the paper explores (and perhaps exposes) the ways in which a commitment to congregational order is being undermined, both by local churches and by connexional gatherings, and how this undermining itself undermines our Baptist identity. Tensions between congregationalism and connexionalism might be lessened with a mutual recognition of the integrity of a congregational dynamic.

An ambipolar poly(diketopyrrolopyrrole-terthiophene)-based field-effect transistor (FET) sensitively detects xylene isomers at low ppm levels with multiple sensing features. Combined with pattern-recognition algorithms, a sole ambipolar FET sensor, rather than arrays of sensors, can discriminate highly similar xylene structural isomers from one another.

The utility of profluorescent nitroxides (PFNs) as sensitive probes to detect early stage photodegradation in a cyclic olefin copolymer, TOPAS®, during both natural aging and accelerated aging under laboratory conditions is reported. PFN additives in TOPAS® capture radicals to form fluorescent adducts as the material degrades. The levels of fluorescence detectable from the polymer reflect the degree of free-radical degradation in the material, with the PFN probes delivering enhanced sensitivity over traditional analytical methods for the detection of photodegradation of TOPAS®. The probes are able to highlight polymer degradation occurring within the oxidation “induction” period, where little change can be observed using infrared spectroscopy; however, their efficacy does not extend far beyond this period. The effective probe lifetime however can be significantly extended through the use of common additives such as the UV absorber (Tinuvin P) and a hindered amine stabiliser analogue (1,1,3,3-tetramethylisoindol-2-yloxyl, TMIO).

The impact of commonly used agrichemicals (Paraquat, Mancozeb, Chlorpyrifos and Sulfur) on the environmental stability of polyethylene films has been evaluated under accelerated photo-oxidative conditions. Paraquat and Mancozeb when applied to unstabilized clear polyethylene film, followed by exposure to UV radiation, resulted in direct attack of the polymer, evident by faster rates of oxidation and shorter times to embrittlement compared to a polyethylene control. Reapplication of these chemicals during exposure, as often occurs in agricultural practice, resulted in even faster degradation. In contrast, Sulfur and Chlorpyrifos did not have a significant effect on the photodegradation of exposed unstabilized polyethylene film. When the polyethylene film was pigmented (white top layer containing rutile titanium dioxide and carbon black in the bottom layer) and stabilized with the addition of hindered amine stabilizers (HAS), differences in oxidation susceptibility were seen with repeated exposure to Paraquat showing the most dramatic effect. This was evident by an increased carbonyl index, decrease in elongation at break and an increase in tensile stress at yield compared to a control film and other agrichemical treatments. These studies enable degradation from accelerated consumption of stabilizers by the agrichemicals (and their degradation products) to be differentiated from enhanced photochemical initiation of the polyethylene degradation.

In response to Stephen Holmes, this paper reviews the Trinitarian contributions of the Cappadocian Fathers and Augustine with the goal, following Robert Jenson and Colin Gunton in particular, of reasserting the key distinctions between them and some aspects of the heritage of these distinctions in Western theology and popular piety. The paper also acknowledges some of their commonalities, including the common inadequacies in their expressions of the doctrine of the Spirit.

This paper describes recent developments in the use of chemiluminescence (CL) and profluorescent nitroxides (PFNs) in probing the “induction period” of polymer oxidation. CL measures the instantaneous rate of reaction of hydroperoxides responsible for initiating degradation and the spreading of oxidation, while PFNs can be used to measure the concentration of alkyl radicals produced in oxidation events and thus provide an integrating sensor for the extent of cumulative damage. The PFN additive acts as an oxidation retarder by competing with oxygen to scavenge the alkyl radicals that generate chain carrying peroxy radicals and so mirrors the performance of hindered amine stabilisers (HAS) in one part of their stabilisation cycle. Using the example of polypropylene (PP) and cis-polyisoprene (PIP) as substrates which can rapidly spread oxidative damage, the factors controlling the reaction of PFNs can be determined from CL and fluorescence as well as infra-red (IR) spectroscopy through the detection of oxidation products as measured by the carbonyl index. Matrix effects on the reactivity are demonstrated using a polyethylene-norbornene copolymer (TOPAS) as carrier for both PIP and the PFN and it is seen that the PFN is a radical scavenger only above Tg of the carrier. When PIP alone is oxidized, the PFN is an integrating sensor for free radical production under ambient conditions for up to twelve months while also stabilizing the polymer. Critically, it is thus able to determine the underlying rate of radical production in the oxidation induction period.

Aircraft coatings are generally multi-layered with both barrier properties and are corrosion inhibitor filled to prevent corrosion. A new technique, automated in situ block face ultramicrotome imaging using an FEG-SEM has been employed for high resolution 3-D imaging of such aircraft coatings. A pristine and a cracked aged coating were visualised by this method clearly showing the coatings microstructure and subsequent crack growth properties. Filler particles were segmented and labelled allowing the coating to be more clearly visualised and enabling statistical particle analysis and meshing. Finally the method was used to investigate the inhibitor leaching properties of four aircraft primers.

Degradation of polypropylene (PP) during melt processing was studied using a novel profluorescence technique. The profluorescent nitroxide probe, 1,1,3,3-tetramethyldibenzo[ e,g ]isoindolin-2-yloxyl (TMDBIO) was added to PP during melt processing to act as a sensor for carbon-centred radicals. Trapping of carbon-centred radicals, formed during degradation of PP, led to an increase in fluorescence emission from TMDBIO adducts. Through analysis of viscosity changes during processing cumulative chain scission degradation was estimated. At processing temperatures of 210 °C or below, fluorescence emission from TMDBIO adducts could be correlated with cumulative chain scissions when the number of chain scissions was small. At higher temperatures, a correlation was not observed most probably due to radical-trap instability rather than decomposition of the TMDBIO. Thus, TMDBIO may be used as a profluorescent sensor for degradation of PP during melt processing when the processing temperature is 210 °C or below.

The profluorescent nitroxide, 1,1,3,3-tetramethyldibenzo[e,g]isoindolin-2- yloxyl (TMDBIO) was investigated as a probe for the radical-mediated degradation of stabilised polypropylene. TMDBIO has been previously shown to be a sensitive probe for free-radical degradation during the thermo-oxidation of unstabilised polypropylene. Here we report on the effect that adding hindered phenol or phosphate stabilisers to polypropylene has on the free-radical sensing ability of TMDBIO during thermo-oxidation. In addition, novel dual-functional, hindered phenol containing profluorescent nitroxides, 5-[2-(4-hydroxy-3,5-di-tert- butylphenyl)ethenyl]-1,1,3,3-tetramethylisoindolin-2-yloxyl (HSTMIO) and its derivatives were investigated as probes for the radical-mediated degradation of polypropylene. These dual-functional probes were shown to be efficient stabilisers for polypropylene during thermo-oxidation at 150 °C in oxygen and sensors of thermo-oxidation during its early stages, in the so-called "induction period".

A direct interrogation, portable analysis technique (portable FT-IR) and a novel environment-monitoring profluorescent sensor for studying aircraft coating degradation have been developed. For the direct interrogation approach, a standard military aircraft paint: 459-line Anzothane flexible polyurethane (lead free) has been used to illustrate a new potential field technique to evaluate coating service lifetime, portable FT-IR. This technique allows direct analysis of chemical changes within the degrading coatings and has the potential to evaluate service lifetime when coupled with advanced statistical analysis methods (chemometrics). The degradation environment monitoring sensors are embodied in a profluorescent environment-sensitive witness patch that may be analysed in-service by a field-deployable fluorescence spectrometer. Accelerated ageing for both the paint and the witness patches has been undertaken and their capabilities as aircraft paint degradation monitors assessed.

The burden of cardiovascular disease (CVD) among patients with diabetes is substantial. Individuals with diabetes are at two- to fourfold increased risk of cardiovascular events compared with age- and sex-matched individuals without diabetes. In diabetic patients over the age of 65 years, 68% of deaths are from coronary heart disease (CHD) and 16% are from stroke (1). A number of mechanisms for the increased cardiovascular risk with diabetes have been proposed, including increased tendency toward intracoronary thrombus formation (2), increased platelet reactivity (3), and worsened endothelial dysfunction (4). The increased risk for cardiovascular events and mortality in patients with diabetes has led to considerable interest in identifying effective means for cardiovascular risk reduction. Aspirin has been shown to be effective in reducing cardiovascular morbidity and mortality in high-risk patients with myocardial infarction (MI) or stroke (secondary prevention) (5). The Food and Drug Administration has not approved aspirin for use in primary prevention, and its net benefit among patients with no previous cardiovascular events is more controversial, for both patients with and without a history of diabetes (5). The U.S. Preventive Services Task Force recently updated its recommendation about aspirin use for primary prevention. The Task Force recommended encouraging aspirin use in men age 45–79 years and women age 55–79 years and not encouraging aspirin use in younger adults. They did not differentiate their recommendations based on the presence or absence of diabetes (6,7). In 2007, the American Diabetes Association (ADA) and the American Heart Association (AHA) jointly recommended that aspirin therapy (75–162 mg/day) be used as a primary prevention strategy in those with diabetes at increased cardiovascular risk, including those who are over 40 years of age or who have additional risk factors (family history of CVD, hypertension, smoking, dyslipidemia, or albuminuria) (8). These recommendations were …

The burden of cardiovascular disease (CVD) among patients with diabetes is substantial. Individuals with diabetes are at two- to fourfold increased risk of cardiovascular events compared with age- and sex-matched individuals without diabetes. In diabetic patients over the age of 65 years, 68% of deaths are from coronary heart disease (CHD) and 16% are from stroke (1). A number of mechanisms for the increased cardiovascular risk with diabetes have been proposed, including increased tendency toward intracoronary thrombus formation (2), increased platelet reactivity (3), and worsened endothelial dysfunction (4). The increased risk for cardiovascular events and mortality in patients with diabetes has led to considerable interest in identifying effective means for cardiovascular risk reduction. Aspirin has been shown to be effective in reducing cardiovascular morbidity and mortality in high-risk patients with myocardial infarction (MI) or stroke (secondary prevention) (5). The Food and Drug Administration has not approved aspirin for use in primary prevention, and its net benefit among patients with no previous cardiovascular events is more controversial, for both patients with and without a history of diabetes (5). The U.S. Preventive Services Task Force recently updated its recommendation about aspirin use for primary prevention. The Task Force recommended encouraging aspirin use in men age 45–79 years and women age 55–79 years and not encouraging aspirin use in younger adults. They did not differentiate their recommendations based on the presence or absence of diabetes (6,7). In 2007, the American Diabetes Association (ADA) and the American Heart Association (AHA) jointly recommended that aspirin therapy (75–162 mg/day) be used as a primary prevention strategy in those with diabetes at increased cardiovascular risk, including those who are over 40 years of age or who have additional risk factors (family history of CVD, hypertension, smoking, dyslipidemia, or albuminuria) (8). These recommendations were …

George Beasley-Murray was commited to ecumenism, and saw clear witness to Baptist distinctives as necessary for this. His plea for a contemporary Baptist confession is re-echoed, with a critique of the Union’s Declaration of Principle which Colwell finds somewhat lacking in important respects.

Background: The aims of this study are to compare the diabetes-related lower extremity amputation (LEA) rate trend in South Carolina (SC) to that of the United States (US) and to determine changes in LEA rates in SC according to age, race, gender, and amputation site. Methods: National Hospital Discharge Survey (NHDS) and SC hospital discharge data for 1996 to 2002 were analyzed. ICD-9-CM codes identified all diabetic patients and occurrences of LEA. Linear regression was used to compare the LEA rate trends between SC and the US. Results: LEA rates are decreasing throughout the study period. The slope is greater in SC compared with US (US slope = - 0.00082; SC slope = -0.0015; P = 0.002), signifying a decrease in LEA rates of 1.5/1000 per year in SC and 0.8/1000 per year in the US. Furthermore, LEA rate decreases in SC are significant throughout all ages, races, genders, and amputation levels. Conclusions: Diabetes-related LEA rates are decreasing in SC more rapidly than in the US. Ongoing community-level education may be assisting in the favorable trends.

Composites with carbon nanotubes are becoming increasingly used in energy storage and electronic devices, due to incorporated excellent properties from carbon nanotubes and polymers. Although their properties make them more attractive than conventional smart materials, their electrical properties have been found to be temperature-dependent which is important to consider for the design of devices. To study the effects of temperature in electrically conductive multi-wall carbon nanotube/epoxy composites, thin films were prepared and the effect of temperature on the resistivity, thermal properties and Raman spectral characteristics of the composite films was evaluated. Resistivity-temperature profiles showed three distinct regions in as-cured samples and only two regions in samples whose thermal histories had been erased. In the vicinity of the glass transition temperature, the as-cured composites exhibited pronounced resistivity and enthalpic relaxation peaks, which both disappeared after erasing the composites' thermal histories by temperature cycling. Combined DSC, Raman spectroscopy, and resistivity-temperature analyses indicated that this phenomenon can be attributed to the physical aging of the epoxy matrix and that, in the region of the observed thermal history-dependent resistivity peaks, structural rearrangement of the conductive carbon nanotube network occurs through a volume expansion/relaxation process. These results have led to an overall greater understanding of the temperature-dependent behaviour of conductive carbon nanotube/epoxy composites, including the positive temperature coefficient effect.

SummaryLongitudinal population-based surveys are widely used in the health sciences to study patterns of change over time. In many of these data sets unique patient identifiers are not publicly available, making it impossible to link the repeated measures from the same individual directly. This poses a statistical challenge for making inferences about time trends because repeated measures from the same individual are likely to be positively correlated, i.e., although the time trend that is estimated under the naïve assumption of independence is unbiased, an unbiased estimate of the variance cannot be obtained without knowledge of the subject identifiers linking repeated measures over time. We propose a simple method for obtaining a conservative estimate of variability for making inferences about trends in proportions over time, ensuring that the type I error is no greater than the specified level. The method proposed is illustrated by using longitudinal data on diabetes hospitalization proportions in South Carolina.

PURPOSE Nearly one third of diabetes cases in the United States is undiagnosed, with mounting evidence that complications accrue even before clinical diagnosis. We wanted to determine whether persons with undiagnosed diabetes have signs of nephropathy and peripheral neuropathy METHODS We examined the prevalence of positive screening tests for nephropathy and peripheral neuropathy in adults aged ≥40 years with undiagnosed diabetes using secondary analysis of survey and examination data from the population-based United States National Health and Nutrition Examination Survey 1999-2002. We defined a positive screening test for nephropathy as a spot urine albumin-creatinine ratio >30.0 mg/g, representing at least microalbuminuria. We defined ≥1 insensate area on Semmes-Weinstein monofilament testing as a positive finding for neuropathy. Undiagnosed diabetes was defined as a combination of no history of diagnosed diabetes and a measured fasting glucose ≥126 mg/dL. We used SUDAAN for χ2 and regression analyses. RESULTS The prevalence of a positive test when screening for nephropathy among those with undiagnosed diabetes was 26.5% compared with 7.1% in those with no diabetes (χ2, P

Accelerated atherosclerosis and the increased risk of thrombotic vascular events in diabetes may result from dyslipidemia, endothelial dysfunction, platelet hyperreactivity, an impaired fibrinolytic balance, and abnormal blood flow. There is also a correlation between hyperglycemia and cardiovascular (CV) events. The importance of platelets in the atherothrombotic process has led to investigation of using antiplatelet agents to reduce CV risk. A meta-analysis conducted by the Antiplatelet Trialists’ Collaboration demonstrated that aspirin reduced the risk of ischemic vascular events as a secondary prevention strategy in numerous high-risk groups, including patients with diabetes. Based on results from placebo-controlled randomized trials, the American Diabetes Association recommends low-dose enteric-coated aspirin as a primary prevention strategy for people with diabetes at high risk for CV events. Clopidogrel is recommended if aspirin allergy is present. There is occasionally a need for an alternative to aspirin or for additive antiplatelet therapy. Aspirin in low doses inhibits thromboxane production by platelets but has little to no effect on other sites of platelet reactivity. Agents such as ticlopidine and clopidogrel inhibit ADP-induced platelet activation, whereas the platelet glycoprotein (Gp) IIb/IIIa complex receptor antagonists block activity at the fibrinogen binding site on the platelet. These agents appear to be useful in acute coronary syndromes (ACSs) in diabetic and nondiabetic patients. A combination of clopidogrel plus aspirin was more effective than placebo plus standard therapy (including aspirin) in reducing a composite CV outcome in patients with unstable angina and non-ST segment elevation myocardial infarction. In a meta-analysis of six trials in diabetic patients with ACSs, intravenous GpIIb-IIIa inhibitors reduced 30-day mortality when compared with control subjects. Results from controlled prospective clinical trials justify the use of enteric-coated low-dose aspirin (81–325 mg) as a primary or secondary prevention strategy in adult diabetic individuals (aged >30 years) at high risk for CV events. Recent studies support the use of clopidogrel in addition to standard therapy, as well as the use of GpIIb-IIIa inhibitors in ACS patients.

In a comparative study, N2+, Ar+ and Ca+ ion implantation was used to modify subcutaneous augmentation material (SAM), a micro-porous form of polytetrafluoroethylene (PTFE) and nonporous PTFE, with a view to assessing the effect of ion implantation on the chemical and physical structure of these materials as well as the effect of porosity on the response to ion implantation. SAM is used as an implant material for reconstructive surgery, and this study is part of a larger investigation into methods of modifying SAM to improve its tissue integration potential. Ion implantation was carried out at an energy of 30 keV, with doses of 1×1015 and 1×1016 ions/cm2. SRIM.2000.39 was used to simulate N2+, Ar+ and Ca+ implantation of PTFE. X-ray photoelectron spectroscopy (XPS) was used for the characterisation of chemical structural changes in the ion-implanted samples, while scanning electron microscopy (SEM) was used for the characterisation of physical structural changes. Rutherford backscattering spectroscopy (RBS) was used to determine the elemental surface composition of Ca+ and Ar+ implanted samples. Advancing and receding water contact angles were measured using the sessile drop method. XPS analysis showed that all ion-implanted samples had undergone chemical structural changes. Some variation was noted between samples implanted with different ions and at different doses. SEM analysis showed that physical structural changes were independent of ion mass with some variation between doses. Water contact angle measurements showed some variation between samples, with nonporous samples showing dose dependent behaviour.

Along the international border separatingthe U.S. (Arizona) and Mexico (Sonora), differencesin the grazing intensity of domestic livestock arecommonly presumed to have created a large differencein vegetation cover between the two countries. Thisvegetation difference is reportedly responsible for anextensive albedo and temperature discontinuity thatmay be affecting regional climate. In this study, weused Landsat Thematic Mapper data to examinetrans-border differences in these two biophysicalparameters. Albedo and radiant temperature estimateswere computed for 25 km-long (east-west) transectsthrough semi-desert grassland on each side of theborder at two different times of year. Only smallaverage trans-border differences in these parameterswere found, and in some cases average albedo andtemperature data were essentially equal on each sideof the border. In addition, we found significantspatial heterogeneity in conditions on both sides ofthe border. These results suggest that, based on asmall sample, it may be difficult to assess whetherthere are significant differences in biophysicalproperties of semi-arid grassland between Arizona andMexico in the vicinity of the border. We concludethat more extensive spatial and temporal sampling iscritical in assessing any possible trans-borderdifferences in average terrain conditions that mightaffect climate, and that this data must be coupledwith more extensive meteorological data to assesswhether a difference in climate also exists.

Summary Only recently are we beginning to understand the complex interplay of factors involved in vascular disease and diabetes. Insulin resistance provides a starting point to explain the many factors that lead to the more severe vascular disease characteristic of diabetes. Insulin resistance syndrome comprises insulin resistance and compensatory hyperinsulinaemia as well as hypertension, dyslipidaemia, macrovascular disease, and increased plasminogen activator inhibitor-1 activity. The development of type 2 diabetes may be viewed as the inability of the pancreas to continue to overcome insulin resistance, even with excessive insulin production.

OBJECTIVE: Microalbuminuria can reflect the progress of microvascular complications and may be predictive of macrovascular disease in type 2 diabetes. The effect of intensive glycemic control on microalbuminuria in patients in the U.S. who have had type 2 diabetes for several years has not previously been evaluated. RESEARCH DESIGN AND METHODS: We randomly assigned 153 male patients to either intensive treatment (INT) (goal HbA(1c) 7.1%) or to standard treatment (ST) (goal HbA(1c) 9.1%; P = 0.001), and data were obtained during a 2-year period. Mean duration of known diabetes was 8 years, mean age of the patients was 60 years, and patients were well matched at baseline. We obtained 3-h urine samples for each patient at baseline and annually and defined microalbuminuria as an albumin:creatinine ratio of 0.03-0.30. All patients were treated with insulin and received instructions regarding diet and exercise. Hypertension and dyslipidemia were treated with similar goals in each group. RESULTS: A total of 38% of patients had microalbuminuria at entry and were evenly assigned to both treatment groups. INT retarded the progression of microalbuminuria during the 2-year period: the changes in albumin:creatinine ratio from baseline to 2 years of INT versus ST were 0.045 vs. 0.141, respectively (P = 0.046). Retardation of progressive urinary albumin excretion was most pronounced in those patients who entered the study with microalbuminuria and were randomized to INT. Patients entering with microalbuminuria had a deterioration in creatinine clearance at 2 years regardless of the intensity of glycemic control. In the group entering without microalbuminuria, the subgroup receiving ST had a lower percentage of patients with a macrovascular event (17%) than the subgroup receiving INT (36%) (P = 0.03). Use of ACE inhibitors or calcium-channel blockers was similarly distributed among the groups. CONCLUSIONS: Intensive glycemic control retards microalbuminuria in patients who have had type 2 diabetes for several years but may not lessen the progressive deterioration of glomerular function. Increases in macrovascular event rates in the subgroup entering without albuminuria who received INT remain unexplained but could reflect early worsening, as observed with microvascular disease in the Diabetes Control and Complications Trial.

OBJECTIVE: The Veterans Affairs Cooperative Study in Type 2 Diabetes Mellitus (VA CSDM) was a multicenter randomized prospective study of 153 male type 2 diabetic patients to assess the ability to sustain clinically significant glycemic separation between intensive and standard treatment arms. A trend toward an excess of combined cardiovascular events in the intensive treatment arm of this trial was reported earlier. The present analysis was done to evaluate the effect of 2 years of intensive glycemic control on the left ventricular (LV) function. RESEARCH DESIGN AND METHODS: The patients were randomized to intensive step treatment with insulin alone or with sulfonylurea (intensive treatment arm [INT], n = 75) or to standard once-daily insulin injection (standard treatment arm [STD], n = 78) treatment. A total of 136 patients (standard treatment arm [STD], n = 70; INT, n = 66) had radionuclide ventriculography at entry and at 24 months for the assessment of LV function. RESULTS: There was no difference in the mean LV ejection fraction (at entry: STD 57.1+/-9.51%; INT 58.1+/-8.7%; at 24 months: STD 57.3+/-10.8%, INT 59.5+/-10.7%), peak filling rate (at entry: STD 2.6+/-0.7 end diastolic volume per second, INT 2.4+/-0.8 end diastolic volume per second; at 24 months: STD 2.7+/-1.0 end diastolic volume per second, INT 2.5+/-0.7 end diastolic volume per second), or time to peak filling rate (at entry: STD 195.3+/-69.5 ms, INT 185.6 +/-62.4 ms; at 24 months: STD 182.6+/-64.8 ms, INT 179.2+/-61.2 ms) between the 2 treatment arms. A subgroup analysis of 104 patients (STD, n = 53; INT, n = 51) that omitted individuals with intervening cardiac events/revascularization or a change in cardioactive medications also showed no difference in the LV function at entry and at 24 months between the 2 groups. Abnormal LV ejection fraction at baseline predicted cardiac events (interval between cardiac beats [RR] = 2.5). CONCLUSIONS: Two years of intensive glycemic control does not affect the LV systolic or diastolic function in patients with type 2 diabetes.

The use of aspirin for the primary prevention of cardiovascular events in patients with type 2 diabetes mellitus is controversial. According to the findings of a Japanese trial, aspirin does not reduce the risk of cardiovascular events in this group of patients, unless they are aged 65 years and above.

Basic and clinical research findings have led to an increased understanding about diabetes and its complications. Therapeutic approaches are now based not only on predicted effects from epidemiologic, correlative, or retrospective analyses, but often on prospective intervention trials comparing a new form of therapy to the standard methods. While this database may never be complete, partially due to the complexity and variability of the diabetic state, we now have excellent data that allow the development of aggressive new guidelines for care. Much of the material presented here reflects the views of the American Diabetes Association, as included in a recent publication (1). These guidelines are under review by a number of other organizations and will be subject to modification for special situations. Thus, the terminology "guidelines," rather than "standards of care," is chosen to indicate the flexibility necessary in developing such recommendations for general usage.

The rationale for intensive insulin therapy and results from major clinical trials in diabetes are reviewed. The Diabetes Control and Complications Trial (DCCT) has shown that intensive insulin therapy will prevent or delay the onset of retinopathy, nephropathy, and neuropathy in type I diabetes. The University Group Diabetes Program (UGDP) and the U.K. Prospective Diabetes Study (UKPDS) have addressed the issue of insulin versus oral agent or diet therapy in people with recently diagnosed type II diabetes. The UGDP showed that effective glycemie control could be achieved with intensive insulin therapy, but no effect on vascular end points was seen. Early data from the UKPDS also suggest that intensive insulin therapy may be more effective in lowering HbA1c toward normal than oral agents or diet. A pressing clinical problem is the question of the use of intensive insulin therapy in type II diabetic individuals who remain hyperglycemie despite pharmacological therapy. A Veterans Affairs Cooperative Study explored the feasibility of using intensive insulin therapy in 153 male type II diabetic patients with these characteristics. A 2% lowering of HbA1c was seen, with no increase in weight gain or in hypoglycemia. However, 40 of 153 patients (26.1%) had cardiovascular events during the 27-month trial; no difference in cardiovascular event rates was seen between the two treatment groups. A long-term multicenter collaborative trial is needed to assess the benefltcrisk ratio of intensive insulin therapy for type II diabetic patients in whom pharmacological therapy failed to provide glycemie management.

This article reviews Jonathan Edwards’ conception of hell as unending punishment in response to those, both then and now, who would propose a conditionalist or annihilationist understanding. While Edwards’ arguments against any form of annihilationism are impressive, his underlying conception of the doctrine of God, implicit in the manner in which he juxtaposes God’s justice and God’s grace, is questioned in the light of the significance of the Cross.

OBJECTIVE It is not clear whether intensive pharmacological therapy can be effectively sustained in non-insulin-dependent diabetes mellitus (NIDDM). The relative risks and benefits of intensive insulin therapy in NIDDM are not well defined. Accordingly, we designed a feasibility study that compared standard therapy and intensive therapy in a group of NIDDM men who required insulin due to sustained hyperglycemia. RESEARCH DESIGN AND METHODS A prospective trial was conducted in five medical centers in 153 men of 60 ± 6 years of age who had a known diagnosis of diabetes for 7.8 ± 4 years. They were randomly assigned to a standard insulin treatment group (one morning injection per day) or to an intensive therapy group designed to attain near-normal glycemia and a clinically significant separation of glycohemoglobin from the standard arm. A four-step plan was used in the intensive therapy group along with daily self-monitoring of glucose: 1) an evening insulin injection, 2) the same injection adding daytime glipizide, 3) two injections of insulin alone, and 4) multiple daily injections. Patient accrual and adherence, glycohemoglobin (HbA1c), side effects, and measurements of endpoints for a prospective long-term trial were assessed. RESULTS Accrual goals were met, mean follow-up time was 27 months (range 18–35 months), and patients kept 98.6% of scheduled visits. After 6 months, the mean HbA1c in the intensive therapy group was at or below 7.3% and remained 2% lower than the standard group for the duration of the trial. Most of the decrease in the mean HbA1c in the intensive group was obtained by a single injection of evening intermediate insulin, alone or with daytime glipizide. By the end of the trial, 64% of the patients had advanced to two or more injections of insulin a day, aiming for normal HbA1c. However, only a small additional fall in HbA1c was attained. Severe hypoglycemia was rare (two events per 100 patients per year) and not significantly different between the groups, nor were changes in weight, blood pressure, or plasma lipids. There were 61 new cardiovascular events in 40 patients and 10 deaths (6 due to cardiovascular causes). CONCLUSIONS Intense stepped insulin therapy in NIDDM patients who have failed glycemic control on pharmacological therapy is effective in maintaining near-normal glycemic control for > 2 years without excessive severe hypoglycemia, weight gain, hypertension, or dyslipidemia. Cardiovascular event rates are high at this stage of NIDDM. A long-term prospective trial is needed to assess the risk-benefit ratio of intensified treatment of hyperglycemia in NIDDM patients requiring insulin.

An ambipolar organic field-effect transistor (OFET) based on poly(diketopyrrolopyrrole-terthiophene) (PDPPHD-T3) is shown by P. Sonar, H. Haick, and co-workers on page 4012 to sensitively detect xylene isomers at low to 40 ppm level in multiple sensing features. Combined with pattern-recognition algorithms, a sole ambipolar FET sensor, rather than arrays of sensors, is able to discriminate highly similar xylene structural isomers from each other.

OBJECTIVE To compare platelet plasminogen activator inhibitor 1 (PAI-1) concentration in type 11 diabetic patients and healthy control subjects. RESEARCH DESIGN AND METHODS We studied a group of 12 diabetic patients whose disease was controlled by diet or sulfonylurea therapy and a group of 17 nondiabetic control subjects. All subjects were free of clinically advanced vascular disease. PAI-1 antigen concentrations were measured in 5 × 108 isolated platelets, which were lysed by 1% Triton X-100. RESULTS Mean platelet PAI-1 was significantly higher in diabetic patients (264 ± 83 ng/5 × 108 platelets) compared with control subjects (202 ±71 ng/5 × 108platelets) (P < 0.05). A significant independent positive correlation was found between platelet PAI-1 concentrations and fasting plasma specific insulin levels in the diabetic patients (r = 0.63, P = 0.03). CONCLUSIONS These findings suggest that 1) a higher platelet PAI-1 concentration may contribute to enhanced thrombosis in type II diabetes and 2) megakaryo-cyte PAI-1 synthesis may be under the control of insulin.

One hundred seventy-eight implants from three systems were placed in 89 type II diabetic patients at 13 Department of Veterans Affairs medical centers. Four failures (2.2 percent) were found at uncovering. The failure rate increased to 7.3 percent at the end of 1 year (nine additional failures). Study patients will be monitored for an additional 4 years. Initial results suggest that type II diabetic patients can be considered for dental implant therapy.

Objective— Patients with NIDDM have a two- to fourfold increased risk of macrovascular disease. The constellation of elevated TGs and decreased HDL cholesterol are recognized as risk factors and constitute the major dyslipidemia in NIDDM. We therefore sought to determine if gemfibrozil (600 mg b.i.d.) was effective in correcting the dyslipidemia of NIDDM. Research Design and Methods– After 8 wk of placebo stabilization, 442 patients from 46 study centers were randomized to double-blind treatment, in a designated 2:1 ratio, 295 received gemfibrozil and 147 received placebo for 20 wk. The primary end point was plasma TG; secondary end points were TC, LDL cholesterol, VLDL cholesterol, HDL cholesterol, and HbA1c. No baseline differences were noted between groups in sex, age, weight, type of diabetic therapy, fasting plasma levels of TGs, HbA1c, or C-peptide. About two-thirds received oral hypoglycemic drugs, one-third insulin Results– TG fell 26.4% in the gemfibrozil group and rose 7.4% in the placebo group (P < 0.023), by an intent-to-treat analysis. When patients who were noncompliant or with inadequate data were excluded, similar results were found—a 30.4% fall with gemfibrozil and a 4.8% increase with placebo (P < 0.0001). TG levels fell within 4 wk and remained low for 20 wk (P < 0.001). Mean HDL cholesterol rose by 4 wk and increased further at 12 wk (8–12%), P < 0.0001. TC fell. We observed a significant rise in LDL cholesterol in both gemfibrozil- and placebo-treated groups, with no significant differences between these groups. Changes in HbA1c were similar in gemfibrozil and placebo groups. No differences were observed in responses in groups treated with insulin and or oral hypoglycemic drugs. Overall AEs that were clinically important occurred in 6.1% in the gemfibrozil group vs. 2.0% in the placebo group (NS). Conclusions– We conclude that gemfibrozil is an effective and safe agent in combating the dyslipidemia of NIDDM, irrespective of type of diabetic therapy.

OBJECTIVE To determine, after 1 yr of follow-up in type II diabetes patients, whether a statistically and clinically significant difference can be achieved in HbA1c between a standard therapy group and an intensively treated group, while maintaining HbA1c levels in both groups within ranges acceptable in regular community practice. Secondary objectives include assessment of patient adherence to protocol, side effects, and accuracy of data collection. RESEARCH DESIGN AND METHODS This is a prospective, randomized, controlled VA CS conducted with 151 patients at five VAMCs. Patients are males, age 40–69 yr, treated at entry with a maximum dose of sulfonylurea or with insulin, exhibiting an HbA1c level > 3 SDs above the normal mean (5.05 + 3 × 0.50 = > 6.55%). Standard control is achieved with insulin and intensive control with a step-up regimen including insulin alone or insulin/glipizide combinations. Education and management of cardiovascular risk factors are handled similarly in both groups. Primary macrovascular end points are nonfatal myocardial infarction, congestive heart failure, stroke, amputation, and cardiovascular death. Primary microvascular end points are appearance and progression of retinopathy, documented by centrally read seven-field-stereo fundus photographs. Other measured indicators include resting and ambulatory ECGs, ventricular function (MUGA scan), serum lipid and apolipoprotein levels, plasma fibrinogen, nonsymptomatic peripheral vasculopathy, neuroautonomic status by heart-beat variation on Valsalva maneuver, and microalbuminuria. CONCLUSIONS This study may be the basis for a long-term trial, involving 1400 patients, to assess the long-term effects of metabolic control on macro- and microvascular end points.