Field Damage Research Articles

Pharmacogenetics and pharmacogenomics in glaucoma therapeutics: the way to personalized therapy.

Pharmacogenetics and pharmacogenomics in glaucoma therapeutics: the way to personalized therapy.

A Fully Coupled Thermomechanical Phase Field Method for Modeling Cracks with Frictional Contact

In this paper, a thermomechanical coupled phase field method is developed to model cracks with frictional contact. Compared to discrete methods, the phase field method can represent arbitrary crack geometry without an explicit representation of the crack surface. The two distinguishable features of the proposed phase field method are: (1) for the mechanical phase, no specific algorithm is needed for imposing contact constraints on the fracture surfaces; (2) for the thermal phase, formulations are proposed for incorporating the phase field damage parameter so that different thermal conductance conditions are accommodated. While the stress is updated explicitly in the regularized interface regions under different contact conditions, the thermal conductivity is determined under different conductance conditions. In particular, we consider a pressure-dependent thermal conductance model (PDM) that is fully coupled with the mechanical phase, along with the other three thermal conductance models, i.e., the fully conductive model (FCM), the adiabatic model (ACM), and the uncoupled model (UCM). The potential of this formulation is showcased by several benchmark problems. We gain insights into the role of the temperature field affecting the mechanical field. Several 2D boundary value problems are addressed, demonstrating the model’s ability to capture cracking phenomena with the effect of the thermal field. We compare our results with the discrete methods as well as other phase field methods, and a very good agreement is achieved.

Follow-up studies of the classical landmark studies in Glaucoma.

It was not until the nineteen nineties that there was scientific evidence for the primary treatment concept of glaucoma, lowering intraocular pressure. The treatment concept of lowering intraocular pressure is now proven by randomized controlled clinical trials (landmark studies). This review provides an overview of the follow-up studies to these landmark studies from the last 18 months. The 20-year data of the ocular hypertension treatment study showed a 49% incidence of primary open-angle glaucoma. The data of this landmark study was used for developing different machine learning algorithms. Bilateral disease, disc hemorrhages, and higher intraocular pressure (IOP) were risk factors for visual field deterioration in the United Kingdom Glaucoma Treatment Study. The Advanced Glaucoma Intervention Trial and the Collaborative Initial Glaucoma Treatment Study identified demographic factors, comorbidity, and clinical variables associated with visual field damage. Analysis was performed on Chinese subsets from the Laser in Glaucoma and Ocular Hypertension Study (LiGHT). Looking at all the follow-up studies to the tube shunt landmark studies, preoperative IOP, neovascular glaucoma, Ahmed implantation, and younger age were predictors of failure. A follow-up study to the Effectiveness in Angle-Closure Glaucoma in Lens Extraction Study showed that patients were ten times more likely to maintain a drop-free target IOP after lens extraction than after laser iridotomy. A superior location for iridotomy results in significantly more significant angle widening than temporal or nasal locations, as shown by a follow-up study to the Zhongshan Angle Closure Prevention Trial using OCT and gonioscopy. The number of published follow-up studies to the landmark studies in glaucoma show the ongoing development of clinical questions in management of glaucoma.

Empirical resilience and vulnerability model of regional group structure considering optimized macroseismic intensity measure

An optimized macroseismic intensity index, which integrates the traditional macroseismic intensity scale and the instrument intensity evaluation model, is proposed to evaluate regional buildings’ empirical resilience and vulnerability. The traditional failure probability of the group structure is modified and improved. The parameters and probability indexes used to assess the resilience and vulnerability of group structure in urban and rural areas are innovatively proposed. The empirical group structure seismic loss data from the actual field investigation of the Jiuzhaigou earthquake in Sichuan Province, China, on August 8, 2017, were statistically analysed, the vulnerability of the sample data was assessed by using the optimized Chinese seismic intensity scale (OCSIS-20), European Macroseismic Scale (EMS-98) and the Modified Mercalli Intensity (MMI), and the assessment and comparison model of multidimensional modal resilience and probability index was established. To improve the rationality and accuracy of typical building resilience in the macrointensity quantification region, a new quantitative model of resilience and vulnerability based on optimizing the macrointensity index and updating the lognormal distribution is proposed, and the group structure resilience comparison models for typical macrointensity standard evaluation are established. The structural vulnerability database of the Jiuzhaigou earthquake is utilized to verify the rationality of the innovative model. Ultimately, field loss inspection and damage mechanism analysis are conducted based on the characteristics of regional structural seismic resilience and the actual vulnerability of the Jiuzhaigou earthquake.

Maize Inbred Mp708 is Highly Susceptible to Western Corn Rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), in Field and Greenhouse Assays.

The western corn rootworm (WCR), Diabrotica vifgirera virgifera LeConte, (Coleoptera: Chrysomelidae) causes significant economic damage in corn production each year. Resistance to insecticides and transgenic corn with Bacillus thuringiensis (Bt), Berliner toxins have been reported throughout the United States Corn Belt. Corn breeding programs for natural resistance against WCR larvae could potentially assist in rootworm management. Root damage and root regrowth of eight corn lines were evaluated in field assays at three different locations. Results indicated the inbred 'Mp708' had the greatest root damage and was significantly greater than damage for the susceptible control, B37×H84. In greenhouse assays, we evaluated four of these lines plus a hybrid expressing the mCry3A Bt toxin for damage. The results indicated that Mp708 had significantly higher root damage when compared to 'CRW3(S1)C6' and 'MIR604'. Despite previous work suggesting otherwise, we conclude that Mp708 is highly susceptible to the WCR larvae based on root damage in field and greenhouse plant assays.

Theory and implementation of sub-model method in finite element analysis

Through finite element analysis (FEA) software to study mechanical performance of a bridge structure is currently a commonly used method. The keys to obtain accurate results are to select the appropriate element type and establish a refine mesh model. With the construction of a large number of kilometer-level long-span bridges in practical projects, the time cost of establishing and analyzing a fine mesh solid finite element model (FEM) of a long-span bridge with complex structure can not be ignored. In order to find the balance between accuracy and efficiency, sub-modeling technique can be used to analyze the bridge structure. It is often thought that the sub-modeling technique is only applicable to shell and solid elements, but in fact it is also applicable to plane frame models. Based on two-dimensional (2-D) beam element model, the theory of sub-model was theoretically deduced. Meanwhile the sub-modeling technique was applied and verified by an example of plane frame model. Furthermore, based on the three-dimensional (3-D) solid FEM of a skew bridge, the influence of mesh size on the calculation accuracy was illustrated. Based on sub-modeling technique of nodal displacements, the results of the global model and the sub-model for the skew bridge were compared and studied in terms of stress field and plastic damage of concrete. It is found that the sub-model technique based on nodal displacements is suitable for solid FEM.

Simplifying the diagnosis of optic tract lesions.

Optic tract lesions (OTL) are often difficult to diagnose. We suggest an algorithm to simplify the often-challenging diagnosis of OTL. Clinical and imaging data were retrospectively collected from the electronic files of 6 patients diagnosed with OTL at a tertiary medical center in 2016-2020. The series included 4 children and 2 adults with an OTL caused by a glioma (n = 5) or motor vehicle accident (n = 1). Magnetic resonance imaging (MRI) revealed a suprasellar glioma involving the chiasm and tract alone (n = 1) and the ipsilateral optic nerve (n = 2) and only optic tract (3). Perimetry showed incongruent homonymous hemianopia in 3 patients. In two patients, perimetry could only be performed in one eye, and demonstrated hemianopia. In one patient perimetry was unreliable. Fundus examination revealed bow-tie atrophy in all patients. On optical coherence tomography (OCT) of the peripapillary retinal nerve fiber layer (RNFL) horizontal thinning was observed in the contralateral eye (n = 6). By presenting the information in a predefined order-visual field damage, OCT RNFL thickness, and MRI-the diagnosis could be easily reached even in children, and when other structures like the chiasm were involved. Fundus photographs easily detect bow tie atrophy in children. Systematic presentation of the data in a predefined order can ease the diagnostic process of OTLs.

Effects of Three Cultural Practices on Drosophila suzukii (Diptera: Drosophilidae) in Open Blueberry Fields in Florida.

Simple SummaryThe spotted-wing Drosophila is an invasive pest of berry fruits in Florida. The pest is difficult to control with pesticides, and resistance is developing. The current study was carried out in north Florida to see if non-pesticidal pest control tactics using three mulching practices could reduce its population density to increase growers’ berries productivity. The experiments were conducted for two years while using two plant-based mulches (short pine needles and pine bark) and one fabric-based mulch in the open blueberry fields. In general, the fly population was reduced within the selected pine bark and black weed fabric mulches. This is the first report of such practices deployed to manage the spotted-wing Drosophila in Florida. We are confident that these selective cultural practices could be utilized in open blueberry fields before berries settings to reduce pest pressure for both conventional and organic blueberry growers in Florida. Indeed, this will increase growers’ berry production and profitability.The spotted-wing Drosophila (SWD), Drosophila suzukii, is native species in Southeast Asia. For over a decade, this invasive pest has been globally expanding. The economic losses to soft fruits and stoned fruits in the United States are increasing every year. Presently, the only viable tool to reduce the SWD population is the continued use of broad-spectrum insecticides. Pesticide resistance is appearing in the populations for the SWD. Organic farmers have limited options to control this pest in open fields. The major goal of this study was to develop cost-effective pest management strategies to manage the SWD using three types of mulches (two plant-based and one fabric-based) to reduce fly population and damage in open blueberry fields in north Florida. The study was conducted in two fruiting seasons (2017 and 2018). The study results demonstrated that the fly trap catches in 2017 shortleaf pine needle mulch had much higher populations (about 2.5-fold) of the SWD than all other treatments. In 2018, the numbers were about 1.7-fold more on shortleaf pine needle mulch than on other treatments. The fine texture of the mulch (pine needles) can easily facilitate the emergence of the SWD if the mulch is not thick enough. Although the pine needles covered the soil surface, it may have been too thin and thus allowed the SWD adults to emerge from the soil without much hindrance. In 2018, a higher population of the SWD was recorded from all the mulching practices. However, there were no significant differences in trap catches between all treatments. In general, the fly population is reduced with the use of pine bark and black weed fabric mulches. This is the first study that reports the effects of three mulches in controlling the SWD populations, which could benefit conventional and organic blueberry growers.

Numerical investigation of the temperature field and frost damages of a frost-penetration tunnel considering turbulent convection heat transfer

Accurate evaluation of tunnel temperature field plays an essential role in anti-freezing measures of cold-region tunnels. The aim of this study is to establish turbulence-based theoretical models for the temperature field of cold-region tunnels and to investigate the temperature field and frost damages of an actual cold-region tunnel with negative mean annual air temperature. A transient convection–conduction heat transfer model with turbulent flow and phase change was established. The proposed theoretical model was validated using model test results. The temperature field and frost damages of the Daban Mountain tunnel were investigated. The influence of global warming on the temperature field was also deeply discussed. The results indicate that for the Daban Mountain tunnel, the freezing circle develops to the radial surrounding rock and simultaneously develops along the longitudinal direction of the tunnel. Permafrost occurs at the tunnel entrance in the 7th year and along the whole tunnel in the 16th year. The formation rate and maximum freezing depth of permafrost is significantly influenced by the mean annual air temperature. The annual air temperature amplitude has significant effect on the formation rate of permafrost but little effect on the maximum freezing depth. Under global warming, the mean annual temperature of the surrounding rock decreases first and then increases. In the early years, the unfrozen surrounding rock freezes yearly and develops into permafrost. However, as the mean annual air temperature rises, the permafrost gradually degenerates into seasonally frozen rock and the maximum freezing depth decreases yearly.

Application of Convolution Neural Network Algorithm Based on Intelligent Sensor Network in Target Recognition of Corn Weeder at Seedling Stage

Grass damage in the seedling corn field has always been an important factor affecting the growth and development of crops. The existence of grass not only compresses the living space of corn seedlings but also easily causes insect damage. Therefore, it is essential for weeding in the seedling corn field. The existing weeding methods usually use manual or chemical herbicide spraying, which is not only time-consuming and laborious but also inefficient. With the development of artificial intelligence and modern agricultural technology, the use of robots for field weeding has become an effective means, which has attracted more and more attention of researchers at home and abroad. Therefore, based on the full investigation of the development of relevant technologies at home and abroad, this paper carried out the research on the real-time target recognition and ranging method of field weeding robot and proposed a target recognition method of weeding corn at the seedling stage by using an intelligent sensor network and deep learning convolution neural network. Among them, the intelligent sensor is mainly used for target ranging and obstacle avoidance, and CNN is mainly used for target recognition. Taking the images of corn seedlings and weeds in the seedling stage under natural environmental conditions as samples, the migration training is carried out through the depth network model of the COCO data set, and the convolution features are shared by the CNN depth network model and Fast-CNN depth network model. VGG and ResNet feature extraction networks are compared. The experimental results show that the CNN depth network model based on this paper has obvious advantages in rape and weed target recognition. The target recognition accuracy of rape and weeds can reach 87.64%, and the recall rate can reach 80.23%. Compared with other models, it has obvious advantages, which proves the effectiveness of this model.

A PZT-Driven 6-DOF High-Speed Micromanipulator for Circular Vibration Simulation and Whirling Flow Generation

Existing micromanipulation methods, whether contact micromanipulation or non-contact micromanipulation, can hardly meet the requirements of low damage and multiple functions in the biomedical field. This study provides a high-speed micromanipulator that can simulate circular vibrations and generate microflow, which could be utilized to actuate non-invasive multiple operations of biological targets at the microscale. We design a PZT-driven 6-DOF micromanipulator with a hybrid structure and flexible hinges. Two 3-PRS parallel modules are serially connected in mirror style to achieve high speed, high accuracy, and a big workspace simultaneously, which enables the highly-controllable circular vibration simulation and strong whirling flow generation. The static, dynamic, and trajectory tracking performances were evaluated. The experimental result showed the 324 × 331 × 40 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> workspace, which was also the range of trajectories that could be generated. Trajectory tracking performance evaluation showed that it could realize ∼200 Hz circular vibration with an error of about 2.4% through open-loop control. Finally, the microflow generation experiment indicated the great potential of the proposed micromanipulator and the method of whirling flow generation in operating the biological targets at the microscale.

Response of Natural Enemies toward Selective Chemical Insecticides; Used for the Integrated Management of Insect Pests in Cotton Field Plots

Sucking pests of cotton (Gossypium hirsutum L.), such as thrips, or Thrips tabaci Lindeman, and jassid, or Amrasca biguttula Ishida, are among the most threatening insect pests to young cotton plants in Pakistan. New chemical insecticides have been trialed to control their damage in commercial fields. Formulations that show good suppression of these pest’s populations, while sparing bio-controlling agents, are always preferred for obtaining better crop yield. Six different commercially available insecticides, namely Fountain® (fipronil and imidacloprid), Movento Energy® (spirotetramat and imidacloprid), Oshin® (dinotefuran), Concept Plus® (pyriproxyfen, fenpyroximate, and acephate), Maximal® (nitenpyram), and Radiant® (spinetoram) were evaluated in the present study to shortlist the best available insecticide against targeted pests. Harmful impacts of selected insecticides were also evaluated against naturally occurring predators, such as spiders and green lacewings (Chrysoperla carnea). Radiant® (spinetoram) and Movento Energy®, respectively, were best at controlling thrips (with 61% and 56% mortality, respectively) and jassid (62% and 57% mortality, respectively) populations during 2018 and 2019. Radiant® proved itself as the best option and showed minimal harmful effects on both major arthropod predators of cotton fields i.e., spiders (with 8–9% mortality) and green lacewings (with 12–16% mortality). Movento Energy® also showed comparatively less harmful effects (with 15–18% mortality) towards natural predatory fauna of cotton crops, as compared to other selective insecticides used in the study. The findings of current study suggest that the judicious use of target-oriented insecticides can be an efficient and predator-friendly management module in cotton fields. However, the impact of these chemicals is also depended on their timely application, keeping in consideration the ETL of pests and the population of beneficial arthropods.

Resistivity Response of Thermally Treated Granite During the Compression Test.

To determine the stress and damage state of rock mass is important for many geotechnical engineering. To study the feasibility of resistivity measurement in characterizing the damage and stress state, the resistivity measurement, uniaxial compression test, and incremental loading–unloading compression test were carried out on granite samples with different porosities (induced by different treatment temperatures). Results show that the resistivity is very sensitive to thermal damage and mechanical damage during compression. The evolution of resistivity can not only quantify thermal damage but also clearly indicate the critical stress (crack closure stress and crack damage stress) and damage stage during compression. In addition, the resistivity evolution was quite different in the pore closure stage, elastic deformation stage, and unstable cracking stage during the loading–unloading process, which is useful in field stress and damage state identification for field monitoring. The conductive mechanism variation during compression was discussed using the Archie equation considering crack volume strain evolution during the mechanical damage process. Overall, the resistivity measurement holds great potential in geotechnical engineering for field monitoring.

Study on flexible surface dielectric barrier discharge plasma film for in situ inactivation of bacteria and viruses

COVID-19 is still pandemic in the world although it has lasted for more than two years, in situ real-time disinfection of curved surfaces in public places is extremely urgent. A flexible plasma film based on surface dielectric barrier discharge is proposed in this study. In situ disinfection effect and the influence of curvature on the performance are studied. The results showed that the film could in situ inactivate a variety of pathogens. Specifically, 10 min plasma treatment results in a log reduction of 3.10, 3.42, and 3.03 for Escherichia coli, Staphylococcus aureus, and vesicular stomatitis virus, respectively. The discharge power and disinfection effect of the film are independent of the curvature, which proves that it can be used for in situ disinfection of curved surfaces. It is speculated that the combined effects of a strong electric field and radical etching physical damage as well as the chemical damage of reactive oxygen and nitrogen species to the protein are the main reasons for the inactivation of pathogens. The inhibition of the film to Omicron type SARS-CoV-2 pseudovirus is 99.3%, and the killing rate to natural bacteria is 94.3%. The film can run for at least 10 h without significant reduction in disinfection effect. In addition, large-scale and digitalization increase the practical potential of a disinfection film. In conclusion, this film is expected to realize in situ real-time disinfection of curved surfaces such as the buttons of the elevator or instrument and door handles, which is of great significance in blocking the spread of COVID-19.

Abundance and Dynamics of the Main Heteroptera Pests of Cocoa Tree in the Orchards of the Department of Méagui (South-West, Côte d’Ivoire)

The capsids Sahlbergella singularis and Distantiella theobromae, the cocoa mosquito Helopeltis sp., and the green bug Bathycoelia thalassina are the main Heteroptera pests causing immense damage in cocoa fields in the department of M&amp;eacute;agui, the main cocoa producing area of C&amp;ocirc;te d&amp;rsquo;Ivoire. The actual study was conducted to assess the spatial and temporal distribution of these pests in this department. From May 2020 to April 2021, the pest abundance and population dynamics were recorded once a month in seven selected cocoa farms in the localities of Yaodankro and S&amp;eacute;rigbangan. Tarping and systematic search methods were used. The results indicated that the three types of insect pests are present and the abundance rates ranging from 20.83% to 42.22% from 15 910 individuals recorded. Capsids were more abundant in the S&amp;eacute;rigbangan orchards than in those of Yaodankro, while the cocoa mosquito and the green bug were more abundant in Yaodankro than in S&amp;eacute;rigbangan. The number of individuals remained relatively high throughout the year except in May-June (months of intense rainfall) where capsid and cocoa mosquito populations were less abundant. Peak populations occurred during the dry season (July, August, February, and March-April) and during the low/medium rainfall season (September and November). The cocoa mosquito and the green bug once considered minor pests were shown to be major pests.

Study on dynamic splitting tensile damage characteristics of basalt fiber reinforced concrete based on AE and DSCM

This paper aims to study the action mechanism of basalt fiber on concrete and the internal damage evolution of basalt fiber reinforced concrete (BFRC) in Brazilian disc splitting tensile tests using acoustic emission (AE) technology and digital speckle correlation method (DSCM). The effects of loading rate and basalt fiber content on splitting tensile failure mode and deformation capacity of BFRC, as well as AE frequency domain characteristics were investigated herein. Then the strain field and local damage factor of BFRC under dynamic splitting tensile load were analyzed based on DSCM. The results indicate that the increase of loading rate and basalt fiber content can change the failure into a complex tensile-shear mixed failure. And the deformation capacity of BFRC can be considerably enhanced by adding a proper amount of basalt fibers. It is also found that the damage degree and damage mechanism of BFRC can be identified by analyzing the wavelet peak frequency of specific frequency range. Furthermore, the crack evolution of BFRC under dynamic splitting tensile load can be reflected well on the change of strain field nephogram of BFRC obtained by DSCM.

Monomethyl auristatin antibody and peptide drug conjugates for trimodal cancer chemo-radio-immunotherapy

Locally advanced cancers remain therapeutically challenging to eradicate. The most successful treatments continue to combine decades old non-targeted chemotherapies with radiotherapy that unfortunately increase normal tissue damage in the irradiated field and have systemic toxicities precluding further treatment intensification. Therefore, alternative molecularly guided systemic therapies are needed to improve patient outcomes when applied with radiotherapy. In this work, we report a trimodal precision cytotoxic chemo-radio-immunotherapy paradigm using spatially targeted auristatin warheads. Tumor-directed antibodies and peptides conjugated to radiosensitizing monomethyl auristatin E (MMAE) specifically produce CD8 T cell dependent durable tumor control of irradiated tumors and immunologic memory. In combination with ionizing radiation, MMAE sculpts the tumor immune infiltrate to potentiate immune checkpoint inhibition. Here, we report therapeutic synergies of targeted cytotoxic auristatin radiosensitization to stimulate anti-tumor immune responses providing a rationale for clinical translational of auristatin antibody drug conjugates with radio-immunotherapy combinations to improve tumor control.

Few-cycle optical field breakdown and damage of gallium oxide and gallium nitride

Both gallium oxide and gallium nitride have great potential for use as high power transparent conducting oxide materials for a wide range of optoelectronic applications. It is, therefore, important to determine the dynamic optical field breakdown for these materials. Here, we report laser damage thresholds for Ga2O3 and GaN using 9 fs few-cycle pulses with a center wavelength near 760 nm. We determine laser-induced damage thresholds (LIDTs) for both single pulse and multi-pulse exposures, with multi-pulse LIDT showing significant reduction compared to single pulse LIDT (in some cases, &amp;gt;50%), possibly due to laser-induced defects. We show that Ga2O3 and GaN have an ultrafast optical field breakdown of 23 and 18 GV/m when nearly polarized along their [010] and [111] planes, respectively, extending their suitability for high power applications to the ultrashort pulse regime. To accurately characterize the excited carrier density criteria in which apparent laser damage occurs, carrier excitation dynamics for the entire laser pulse interaction were simulated using a modified Keldysh ionization model. For the measured single-shot threshold fluences, the plasma critical density was surpassed by 2 orders of magnitude and 2D finite-difference time-domain simulations were employed to understand the pulse interaction near the surface.

Impact of Smoking on Visual Field Progression in a Long-term Clinical Follow-up

To investigate the effect of smoking on rates of progressive visual field (VF) damage over time in glaucoma. Retrospective cohort study. Five hundred eleven eyes of 354 patients with glaucoma followed up from multicenter glaucoma registries. In this longitudinal study, 354 patients with primary open-angle glaucoma with a minimum of 3 years of follow-up and 5 VF tests were enrolled from the Diagnostic Innovations in Glaucoma Study and the African Descent and Glaucoma Evaluation Study. Univariate and multivariate linear mixed models were used to investigate the effects of smoking on rates of 24-2 VF mean deviation loss. Visual field progression was defined using pointwise linear and significant negative VF mean deviation loss. Logistic regression was used to identify baseline factors and whether different levels of smoking intensity were associated with VF progression. Kaplan-Meier survival analysis and the log-rank test were used to compare the cumulative risk ratio of progression between smoker and never smoker groups. Visual field progression. Five hundred eleven eyes of 354 patients were included over the median follow-up of 12.5 years. Median baseline age was 64.8 years. Of the 354 patients, 124 (35%) were Black, and 149 (42.1%) and 168 (59.8%) had reported a history of smoking or alcohol consumption, respectively. In a multivariate model, higher smoking intensity was associated with faster VF loss (coefficient, -0.05 decibels (dB)/year per 10 pack-years; 95% confidence interval [CI], -0.08 to -0.01 dB/year per 10 pack-years; P= 0.010). Developing VF progression in eyes of heavy smokers (≥ 20 pack-years) was 2.2 times more than in eyes of patients without smoking history (odds ratio, 2.21; 95% CI, 1.02-4.76; P= 0.044). Statistically significant differences were found between heavy smokers (≥ 20 pack-years) and never smokers by Kaplan-Meier analysis (P= 0.011, log-rank test). Heavy smokers are more likely to sustain VF loss in eyes with glaucoma. The prospective longitudinal design of this study supports the hypothesis that levels of smoking may be a significant predictor for glaucoma progression. Additionally, this information can be used for clinically relevant tobacco prevention and intervention messages.

Threat to fixation and vision-related quality of life in early open-angle glaucoma - results from the Glaucoma Intensive Treatment Study.

To determine the effect of glaucomatous visual field (VF) damage close to the point of fixation, called threat-to-fixation (TTF), on vision-related quality of life (VRQoL) in open-angle glaucoma. A total of 239 patients from the Glaucoma Intensive Treatment Study (GITS) were included in this analysis. The second VF of patients with newly diagnosed primarily early glaucoma was evaluated for the presence or absence of TTF. TTF was defined as VF loss including one or more of the four innermost test points depressed at p< 1% in the total deviation probability map of Humphrey 24-2 SITA Standard visual fields. VRQoL was evaluated using Rasch-analysed National Eye Institute Visual Function Questionnaire 25 (NEI VFQ-25) scores. The correlation between VRQoL and TTF was evaluated using uni- and multivariable regression analyses. TTF was present in at least one eye in 115 patients (48%); located in the superior hemifield alone in 47% (54 of 115), in the inferior hemifield alone in 23% (27 of 115), and in 30% (34 of 115) in both hemifields. The median Rasch-calibrated NEI VFQ-25 scores were identical when comparing patients with TTF (VRQoL score 66, 95% CI: 23-100) and those with no-TTF (VRQoL score 66, 95% CI: 21-100) (p= 0.925). Neither the presence of TTF (R2 = -0.004, p= 0.968) nor the location of TTF (R2 = 0.023, p= 0.103) was significantly correlated to Rasch-calibrated NEI VFQ-25 scores. The presence of TTF did not influence VRQoL, as measured by the NEI-VFQ-25, in this relatively large group of patients with mainly early glaucoma.