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To reach the Paris Agreement, societies need to increase the global terrestrial carbon sink. There are many climate change mitigation solutions (CCMS) for forests, including increasing bioenergy, bioeconomy, and protection. Bioenergy and bioeconomy solutions use climate-smart, intensive management to generate high quantities of bioenergy and bioproducts. Protection of (semi-)natural forests is a major component of “natural climate solution” (NCS) since forests store carbon in standing biomass and soil. Furthermore, protected forests provide more habitat for biodiversity and non-wood ecosystem services (ES). We investigated the impacts of different CCMS and climate scenarios, jointly or in isolation, on future wood ES, non-wood ES, and regulating ES for a major wood provider for the international market. Specifically, we projected future ES given by three CCMS scenarios for Sweden 2020–2100. In the long term, fulfilling the increasing wood demand through bioenergy and bioeconomy solutions will decrease ES multifunctionality, but the increased stand age and wood stocks induced by rising greenhouse gas (GHG) concentrations will partially offset these negative effects. Adopting bioenergy and bioeconomy solutions will have a greater negative impact on ES supply than adopting NCS. Bioenergy or bioeconomy solutions, as well as increasing GHG emissions, will reduce synergies and increase trade-offs in ES. NCS, by contrast, increases the supply of multiple ES in synergy, even transforming current ES trade-offs into future synergies. Moreover, NCS can be considered an adaptation measure to offset negative climate change effects on the future supplies of non-wood ES. In boreal countries around the world, forestry strategies that integrate NCS more deeply are crucial to ensure a synergistic supply of multiple ES.

With the sudden upswing in digitization, usage of Android smartphones has evidently become conventional and common. Nevertheless, such extensive popularity of Android systems comes with a major trade-off between usage and security. Time and again, it has been proven that the existence of malicious applications leverage permissions given by the Android systems in order to compromise them. However, there exist certain combinations of permission sets that could potentially lead to such attacks. To address this, we propose a two-layer architecture, where each layer has an implicit handshake with a Machine Learning ensemble model, that aims at vulnerability detection as well as classification of these detected vulnerabilities into one among the three levels of severity – High Risk, Medium Risk and Low Risk. Efficiency of the proposed system has been evaluated against existing Machine Learning based models such as K-Nearest Neighbors (KNN), Decision Tree Algorithms and Multi-Layered Perceptron (MLP) on an Android Permission-Based Dataset. Results show that our proposed model outperforms the existing approaches, which has been quantitatively evaluated using accuracy and F1-score.

Objectives To study the intraoperative morphology of the glenoid labrum and capsule in recurrent shoulder dislocation and to study the relationship between the number of dislocations and the changes in the glenoid and labrum. Methods Over a period of 18 months, 108 patients with traumatic anterior dislocations were included in the study, of which 102 men and 6 women with mean age of 33.4yrs range from 18 to 45. The patients with bony bankart, other labral lesions, ligamentous laxity, SLAP tear were excluded from the study. All the patients underwent arthroscopic bankart repair. We have classified the morphology of labrum and capsule on their appearance intraoperatively. Labrum is named as Normal, Desiccated or Shredded and Capsule as Normal or Damaged. Results Six varieties of appearances were observed. Namely, Normal capsule and Normal labrum (NN), Normal capsule and Desiccated labrum (ND), Normal capsule and Shredded labrum (NS), Damaged capsule and Normal labrum (DN), Damaged capsule and Desiccated labrum(DD), Damaged capsule and Shredded labrum(DS). Among them, DD (33.3%) and DS (29.6%) variety had highest number of dislocations suggesting the labrum and capsule lose normal anatomy with more recurrence of dislocations. Conclusion These findings support that reproducing normal anatomy after surgical repair is possible when the intervention is done sooner than later. Level of evidence III.

Bioassay of biocontrol agents and fungicides against Maize Banded Leaf and Sheath Blight caused by Rhizoctonia solani showed inhibition. Among the biocontrol agents, Bacillus subtilis and among the fungicides Hexaconazole was found to be effective under field conditions with the percent disease incidence of 2.25% and 3.00% respectively over control 10.45%. Seed treatment (4g/kg) and soil application (2.5kg/ha) of Bacillus subtilis recorded 78.46% reduction in sheath blight incidence and highest grain yield of 6.7t/ha. Foliar spraying of Hexaconazole (0.2%) showed 71.30% reduction and grain yield of 6.4t/ha. Hence, seed treatment and soil application of Bacillus subtilis is considered to be effective against BLSB under field condition. Seed treatment and soil application of Bacillus subtilis, Foliar spraying of Hexaconazole may be recommended for Banded Leaf and Sheath Blight of Maize.

Background: Gastrointestinal neuroendocrine tumors are rare slow-growing tumors with distinct histological, biological, and clinical characteristics that have increased in incidence and prevalence in the last few decades. This study is aimed to find out the incidence of neuroendocrine tumors among the gastrointestinal tumors and to grade gastrointestinal neuroendocrine tumors. Materials and Methods: A total of 119 cases of gastrointestinal tumors of gastrointestinal neuroendocrine was included in the study. The paraffin blocks were retrieved and slides were stained with routine Hematoxylin and Eosin, synaptophysin, chromogranin, and Ki67. The histologic grading was done based on mitosis and Ki-67 index as per WHO 2017 classification. Results: Out of 119 cases of Gastrointestinal Tract tumor, 13 (10.92%) constituted neuroendocrine tumors. Duodenum was the most common site (38%) followed by the appendix (23%). The majority (1.9%) of the cases were categorized as of grade 1 followed by 2.3% of grade 2 and 1.19% of grade 3. Immunohistochemically, chromogranin, and synaptophysin were strongly expressed in all ten cases of neuroendocrine tumors. The Ki67 labeling index was 20 % in one case. Conclusions: The incidence of gastrointestinal neuroendocrine tumors is on the rise. They should be considered in developing a differential diagnosis. Hence use of diagnostic modalities such as immunohistochemistry should be implemented for better treatment.

The ataxia-telangiectasia mutated (ATM) protein kinase is, as the name implies, mutated in the human genetic disorder ataxia-telangiectasia (A-T). This protein has its “finger in many pies”, being responsible for the phosphorylation of many thousands of proteins in different signaling pathways in its role in protecting the cell against a variety of different forms of stress that threaten to perturb cellular homeostasis. The classical role of ATM is the protection against DNA damage, but it is evident that it also plays a key role in maintaining cell homeostasis in the face of oxidative and other forms of non-DNA damaging stress. The presence of ATM is not only in the nucleus to cope with damage to DNA, but also in association with other organelles in the cytoplasm, which suggests a greater protective role. This review attempts to address this greater role of ATM in protecting the cell against both external and endogenous damage.

Females are endowed at birth with a fixed reserve of oocytes, which declines both in quantity and quality with advancing age. Understanding the molecular mechanisms regulating oocyte quality is crucial for improving the chances of pregnancy success in fertility clinics. In vitro culture systems enable researchers to analyse important molecular and genetic regulators of oocyte maturation and fertilisation. Here, we describe in detail a highly reproducible technique for the isolation and culture of fully grown mouse oocytes. We include the considerations and precautionary measures required for minimising the detrimental effects of in vitro culture conditions. This technique forms the starting point for a wide range of experimental approaches such as post-transcriptional gene silencing, immunocytochemistry, Western blotting, high-resolution 4D time-lapse imaging, and in vitro fertilization, which are instrumental in dissecting the molecular determinants of oocyte quality. Hence, this protocol serves as a useful, practical guide for any oocyte researcher beginning experiments aimed at investigating important oocyte molecular factors. Graphic abstract: [Image: see text] A step-by-step protocol for the isolation and in vitro culture of oocytes from mice.

Females are endowed at birth with a fixed reserve of oocytes, which declines both in quantity and quality with advancing age. Understanding the molecular mechanisms regulating oocyte quality is crucial for improving the chances of pregnancy success in fertility clinics. In vitro culture systems enable researchers to analyse important molecular and genetic regulators of oocyte maturation and fertilisation. Here, we describe in detail a highly reproducible technique for the isolation and culture of fully grown mouse oocytes. We include the considerations and precautionary measures required for minimising the detrimental effects of in vitro culture conditions. This technique forms the starting point for a wide range of experimental approaches such as post-transcriptional gene silencing, immunocytochemistry, Western blotting, high-resolution 4D time-lapse imaging, and in vitro fertilization, which are instrumental in dissecting the molecular determinants of oocyte quality. Hence, this protocol serves as a useful, practical guide for any oocyte researcher beginning experiments aimed at investigating important oocyte molecular factors. Graphic abstract: A step-by-step protocol for the isolation and in vitro culture of oocytes from mice.

Premature loss of ovarian activity before 40 years of age is known as primary ovarian insufficiency (POI) and occurs in ∼1% of women. A more subtle decline in ovarian activity, known as premature ovarian ageing (POA), occurs in ∼10% of women. Despite the high prevalence of POA, very little is known regarding its genetic causation. Senataxin (SETX) is an RNA/DNA helicase involved in repair of oxidative stress-induced DNA damage. Homozygous mutation of SETX leads to the neurodegenerative disorder, ataxia oculomotor apraxia type 2 (AOA2). There have been reports of POI in AOA2 females suggesting a link between SETX and ovarian ageing. Here, we studied female mice lacking either one (Setx+/−) or both (Setx−/−) copies of SETX over a 12- to 14-month period. We find that DNA damage is increased in oocytes from 8-month-old Setx+/− and Setx−/− females compared with Setx+/+ oocytes leading to a marked reduction in all classes of ovarian follicles at least 4 months earlier than typically occurs in female mice. Furthermore, during a 12-month long mating trial, Setx+/− and Setx−/− females produced significantly fewer pups than Setx+/+ females from 7 months of age onwards. These data show that SETX is critical for preventing POA in mice, likely by preserving DNA integrity in oocytes. Intriguingly, heterozygous Setx loss causes an equally severe impact on ovarian ageing as homozygous Setx loss. Because heterozygous SETX disruption is less likely to produce systemic effects, SETX compromise could underpin some cases of insidious POA.

Using an in vivo model of DNA damage involving Senataxin knockout mice along with in vitrogenotoxic treatments, Subramanian et al. identify a DNA damage response in oocytes that builds slowly following damage induction and is mediated by increased APC-Cdh1–mediated cyclin B1 proteolysis., In mitotic cells, DNA damage induces temporary G2 arrest via inhibitory Cdk1 phosphorylation. In contrast, fully grown G2-stage oocytes readily enter M phase immediately following chemical induction of DNA damage in vitro, indicating that the canonical immediate-response G2/M DNA damage response (DDR) may be deficient. Senataxin (Setx) is involved in RNA/DNA processing and maintaining genome integrity. Here we find that mouse oocytes deleted of Setx accumulate DNA damage when exposed to oxidative stress in vitro and during aging in vivo, after which, surprisingly, they undergo G2 arrest. Moreover, fully grown wild-type oocytes undergo G2 arrest after chemotherapy-induced in vitro damage if an overnight delay is imposed following damage induction. Unexpectedly, this slow-evolving DDR is not mediated by inhibitory Cdk1 phosphorylation but by APC-Cdh1–mediated proteolysis of the Cdk1 activator, cyclin B1, secondary to increased Cdc14B-dependent APC-Cdh1 activation and reduced Emi1-dependent inhibition. Thus, oocytes are unable to respond immediately to DNA damage, but instead mount a G2/M DDR that evolves slowly and involves a phosphorylation-independent proteolytic pathway.

BACKGROUND In adult epilepsy patients, nonadherence to treatment regimes has been found to be associated with high morbidity, raised mortality and higher health care costs. The present study was undertaken with an aim to evaluate the medication compliance among patients undergoing treatment for epilepsy and study the factors affecting medication compliance. MATERIALS AND METHODS The present study was carried out as a cross sectional study among 100 patients diagnosed with seizure disorders who are already on treatment for a period of at least six months. Drug noncompliance was studied with the help a self-reported questionnaire which was derived from the Brief Medication Questionnaire. The items in the questionnaire recorded information regarding: awareness of drug therapy in terms of dose, timings and name of the drugs, missed medication, factors affecting compliance, aids to compliance, frequency of drug default and relapse. All data was entered in Epidata and statistical analysis was done using the software SPSS version 22.0. Chi square test was applied to test for statistical significance in difference between proportions. A p value

The growth rate of most tree species in boreal forests will increase with changing climate. This increase is counterbalanced by an increased risk of damage due to extreme weather events. It is beli...

Background: Tuberculous, parapneumonic and traumatic loculated pleural-effusions pose therapeutic challenges due to resultant pleural-thickening and compromised lung-function for life. Tuberculosis is widely prevalent in developing countries, necessitating appropriate, effective, and economical treatment for loculated pleural-effusion to reduce the burden and sequelae. Objective: An uncontrolled and blind before-after intervention study to determine the effectiveness of intrapleural fibrinolytic therapy (IPFT) using urokinase in loculated pleural effusions was conducted at a tertiary-care respiratory center after obtaining approval and written informed consent. Methods: Fifty-one patients with loculated pleural effusion were administered with repeated cycles of three doses of 1 Lakh IU of urokinase intrapleurally until complete drainage of pleural fluid. Pre- and post-IPFT clinical and radiological responses were compared using removal of fluid, ultrasound, and chest radiography were compared. The Kolmogorov-Smirnov test and paired t test with significance at a P value less than 0.05 were applied to test statistically significant differences in proportions and means, respectively. Results: Tuberculosis was the most common etiology leading to loculated pleural effusion (80%), and 82.4% of tuberculosis patients required at least two cycles of IPFT. Complete resolution in chest radiograph after IPFT was observed in 80.4% of patients. Chest pain (13.7%) and fever (9.8%) were the most common undesired effects associated with IPFT. A statistically significant reduction in mean intrapleural fluid levels pre- and post-IPFT from 184±81 ml to 67±52 ml was observed. Conclusion: IPFT with urokinase is an effective treatment modality in patients with post-tubercular loculated pleural effusions. IPFT has minimal and tolerable undesired effects and prevents sequelae such as pleural thickening and consequent compromise of respiratory function.

New mortality models were developed for the purpose of improving long-term growth and yield simulations in Finland, Norway, and Sweden and were based on permanent national forest inventory plots from Sweden and Norway. Mortality was modelled in two steps. The first model predicts the probability of survival, while the second model predicts the proportion of basal area in surviving trees for plots where mortality has occurred. In both models, the logistic function was used. The models incorporate the variation in prediction period length and in plot size. Validation of both models indicated unbiased mortality rates with respect to various stand characteristics such as stand density, average tree diameter, stand age, and the proportion of different tree species, Scots pine ( L.), Norway spruce ( (L.) Karst.), and broadleaves. When testing against an independent dataset of unmanaged spruce-dominated stands in Finland, the models provided unbiased prediction with respect to stand age.Pinus sylvestrisPicea abies

The annual growth rates in Swedish forests are higher than the annual harvest rates, and this has resulted in high rates of carbon sequestration in the Swedish forestry sector. Any factor that tends to reduce growth rates also has the potential to reduce forest carbon sequestration rates, and ozone may be one such factor. The aim of this study was to estimate to what extent the occurrence of elevated tropospheric ozone concentrations can negatively affect carbon sequestration by Swedish forest ecosystems. The net primary production (NPP) of Swedish forests was simulated, using the 3-PG model, for representative forest stands in six different geographical zones across Sweden, with and without assumed negative impacts of ozone. Ozone impacts were derived from dose-response relationships, calculated from open-top chamber experiments with young trees. The results of the 3-PG simulations showed that the NPP was generally higher in the A2 and B2 Intergovernmental Panel on Climate Change (IPCC) future climate scenarios, as compared to the current climate, for all tree species and in all geographical zones across Sweden. Biomass production was reduced by 4.3‐15.5% for conifers (Norway spruce (Picea abies L) and Scots pine (Pinus sylvestris L) and by 1.4‐4.3% for birch (Betula pendula Roth and Betula pubescence Ehrh) under ambient ozone conditions as compared to the preindustrial ozone level. The greatest reduction in biomass was found in southern Sweden. Biomass was reduced by similar percentage value in future climate scenarios as that in the current climate.

The growth rate of most tree species in boreal forests will increase with changing climate. This increase is counterbalanced by an increased risk of damage due to extreme weather events. It is believed that the risk of storm damage will increase over time, especially if forests continue to be managed as they are today. In this study, a new landscape-level hybrid forest growth model 3PG-Heureka was developed and simulations were performed to predict the damage caused by storm events in Kronoberg county, over a period of 91 years (2010–2100) with different alternative management regimes under various climatic scenarios (historic, RCP4.5 and RCP8.5). The results indicate that damage caused by storm events could drastically reduce the annual volume increment and annual net revenue obtained from forest landscapes if current forest management regimes are used. These problems can be reduced by adopting alternative management strategies involving avoiding thinning, shorter rotation periods and planting alternative tree species. Alternative management strategies could potentially improve annual volume increments and net revenue obtained while reducing storm-felling. Planting Scots pine instead of Norway spruce across the landscape to minimize storm damage is predicted to be less effective than reducing rotation periods.

Here we investigate whether the presence of germinal vesicle-stage oocytes (GV&minus, oocytes) reflects poor oocyte developmental competence (or quality). This was a prospective, non-randomised, cohort pilot-study involving 60 patients undergoing in vitro fertilization/ intracytoplasmic sperm injection for whom complete pregnancy outcome data were available. Patients in whom GV&minus, oocytes were retrieved (GV+) at transvaginal oocyte retrieval (TVOR) were compared with those from whom no GVs were retrieved (GV&minus, ). We found that GV+ (n = 29) and GV&minus, (n = 31) patients were similarly aged (35.4 vs. 36.4 years, p = 0.446). GV+ patients had a mean of 2.41 &plusmn, 2.03 GVs and comparable yields of MII oocytes to GV&minus, patients (11 &plusmn, 6.88 vs. 8.26 &plusmn, 4.84, p = 0.077). Compared with GV&minus, patients, GV+ patients had markedly lower implantation rates (11.8% vs. 30.2%, p = 0.022) as well as oocyte utilisation rates for clinical pregnancy (2.3% vs. 6.8%, p = 0.018) and live-birth (1.9% vs. 5.7%, p = 0.029). DNA damage levels measured using &gamma, H2AX immunostaining were not different in oocytes from women &lt, 36 years versus those &ge, 36 years (p = 0.606). Thus, patients who have GV&minus, stage oocytes at TVOR exhibit poor oocyte quality reflected in reduced per-oocyte pregnancy success rates and uniformly high levels of oocyte DNA damage.

While climate change is expected to increase the growth rates of most tree species in Sweden in the future, during this period, there are also increased risks of tree damage due to various risk factors associated with climate change. Therefore, it is necessary to develop adaptive management measures in order to exploit the benefits of climate change and minimize the damage resulting from these risk factors. In this thesis, the interactive effects of future climate change and various risk factors associated with the future climate such as storms, environmental pollutants, pests and pathogens such as root rot and bark beetle on growth and yield of important tree species in Swedish forestry such as Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestnis L.) and birch (Betula spp) are investigated and possible adaptive management measures are proposed. Simulations of a representative Norway spruce stand in southern Sweden performed using the empirical Heureka-Standwise model (Paper I) showed that forest management practices such as changing the thinning regime, shortening rotation periods, and switching to exotic tree species like hybrid aspen and hybrid larch could effectively reduce damage caused by risk factors and be financially rewarding. Standlevel simulations of six representative stands across Sweden using the ozone parameterized process-based model 3-PG showed that future growth and biomass production could be adversely affected by increasing tropospheric ozone concentrations (Paper II). However, the reduction in growth and biomass production was much lower than the increase due to climate change in all parts of Sweden other than the south. A new landscape-level hybrid model 3PG-Heureka was developed, parameterised and evaluated for Kronoberg county, Sweden (Paper III). The overall performance of the model was satisfactory with highest average error content of 1.5%. The hybrid model’s predictions under the future climate scenarios indicated that the storm events could drastically affect the growth and economy of forest landscape in Kronoberg county if the current forest management remains unchanged (Paper IV). Adaptive management regimes featuring shorter rotation periods were predicted to improve annual volume increments and net revenue while reducing storm-felling under two future climate scenarios (RCP4.5 and RCP8.5) but replacing Norway spruce with Scots pine was found to be less effective than reducing the rotation period.

We study the empirical evidence on the relationship between the conditional probability of being fired in the event of poor performance (termination risk) and managerial risk-taking. Previous research has focused on compensation risk only and shown that it has a negative effect on risk-taking. We find that termination risk reduces managerial risk taking similarly. Firms that are more likely to fire their managers for poor performance have significantly lower volatility of stock returns. Further, the positive effect of the convexity of the manager's compensation contract on risk taking is also lower at firms where termination risk is high. A 10% increase in the conditional termination propensity results in 5%-22% reduction in stock return volatility for the median firm in our sample.

In many economic settings, faster learning is achievable only through greater exposure to risk. We study this conflict in the context of project choice, where a risk-averse agent must choose whether to invest in two projects of the same type (focus) or of different types (diversification). Focus enables faster learning across periods, but is riskier due to common type-specific shocks. Optimal choice involves balancing these two considerations. We show that focus is preferred for intermediate learning speeds, and that higher prior uncertainty may encourage focus. Thus, what matters for the focus-diversification choice is not only the level of risk, but also whether the risk is permanent or can be “learned away.”

Even though the growth rates of most tree species in Sweden is expected to increase in the near future as a result of climate change, increased risks of damage by storms and various pests and pathogens, notably root rot and bark beetles, may also occur. Thus, forest management practices such as changes to thinning regimes, reductions in rotation lengths, and switching to other species (native or exotic) may represent adaptive management strategies to increase the resistance and resilience of Swedish forests to climate change. Clearly, thorough analyses examining the effects of anticipated climatic changes on damage levels, and the potentially relieving effects of possible management adaptations are needed before implementing such changes. In this study, damage caused by storms, root rot and bark beetles (single and in various combinations) under selected climate and management scenarios were simulated in Norway spruce (Pice abies L. Karst) stands. The results indicate that reductions in thinning intensity and rotation lengths could improve both volume production and profitability in southern Sweden. In addition, cultivation of rapidly growing species, such as hybrid larch (Larix × marschlinsii Coaz.) and hybrid aspen (Populus tremula L. × P. tremuloides Michx.), could be as profitable as Norway spruce cultivation, or even more profitable. However, slow-growing species, such as Silver birch (Betula pendula Roth), Downy birch (Betula pubescens Ehrh.) and European beech (Fagus sylvatica L.) indicated low economic output in terms of Land Expectation Value.

Even though the growth rates of most tree species in Sweden is expected to increase in the near future as a result of climate change, increased risks of damage by storms and various pests and pathogens, notably root rot and bark beetles, may also occur. Thus, forest management practices such as changes to thinning regimes, reductions in rotation lengths, and switching to other species (native or exotic) may represent adaptive management strategies to increase the resistance and resilience of Swedish forests to climate change. Clearly, thorough analyses examining the effects of anticipated climatic changes on damage levels, and the potentially relieving effects of possible management adaptations are needed before implementing such changes. In this study, damage caused by storms, root rot and bark beetles (single and in various combinations) under selected climate and management scenarios were simulated in Norway spruce (Pice abies L. Karst) stands. The results indicate that reductions in thinning intensity and rotation lengths could improve both volume production and profitability in southern Sweden. In addition, cultivation of rapidly growing species, such as hybrid larch (Larix × marschlinsii Coaz.) and hybrid aspen (Populus tremula L. × P. tremuloides Michx.), could be as profitable as Norway spruce cultivation, or even more profitable. However, slow-growing species, such as Silver birch (Betula pendula Roth), Downy birch (Betula pubescens Ehrh.) and European beech (Fagus sylvatica L.) indicated low economic output in terms of Land Expectation Value.

Fan broadband is one of the dominant noise sources on an aircraft engine, particularly at approach. The dominant noise generation mechanism is due to turbulent- aerofoil interaction noise (TAI). This thesis investigates the effect of changes in 2D aerofoil geometry on TAI noise. The main focus of this thesis is to attempt to reduce it through the development of innovative leading edge geometries. The first two chapters of the thesis deals with an experimental and numerical investigation into the effect of aerofoil geometry on interaction noise on single aerofoils and on cascades. Consistent with previous work, they show that variations in aerofoil parameters, such as aerofoil thickness, leading edge nose radius and camber, produce only a small changes in broadband interaction noise at approach conditions. Subsequent chapters deal with the development of innovative leading edge serration profiles aimed at reducing interaction noise. Chapter 4 is a detailed study into the limitations of single-wavelength serrations in reducing interaction noise. The optimum profile is identified. Chapters 5, 6 and 7 all deal with the development of innovative profiles that can provide up to 10dB of additional noise reductions compared to single-wavelength serrations. For each of the profiles investigated a simple model is developed to aid the understanding of their interaction mechanism.

Reliability is of paramount importance to just about any embedded system firmware. This paper presents the out–in methodology (OIM), a new reliability-driven approach to developing such a system, which is intended to detect static and, more importantly, dynamic errors much faster than the usual firmware development methods. In this approach, the core functionality is developed together with an interface software that is used specifically for testing the core functionality. This paper describes the use of this approach in a real life situation and discusses the benefits, potential pitfalls, and other possible application areas.

IEEE-488.2 interface (or popularly known as GPIB interface) -based instruments are very common in the test and measurement industry. The most important characteristics of the firmware for such instruments are small code size and ease of implementation and maintenance. Object-oriented (OO) techniques can be used to exploit their inherent advantages and the paper demonstrates the design of firmware for an IEEE-488.2-based instrument using OO techniques. The advantages of encapsulation allow for ease of comprehension besides ease of implementation and maintenance. This design was used to implement the firmware in a high-end test and measuring instrument and the advantages that ensued are discussed. As a consequence, an inadequacy in the IEEE-488.2 standard was detected which is also pointed out in the paper.

We adopt a comprehensive approach to studying dividend omissions to better understand the motivation behind this important policy decision. We find that poor operating performance, poor financial flexibility, high investment and increased risk are factors that affect the likelihood of a dividend omission. Not all dividend omissions, however, are the same. For 25% of dividend omitting firms, the omission signals a quick turnaround in their operating performance and results in a resumption of dividends within three years from the omission. Our analysis suggests these firms use the dividend omission strategically to improve their financial flexibility, allowing them to pursue valuable investment opportunities. The remaining firms continue to be financially constrained and under-perform their peers after the omission. One possible explanation for this divergence in performance is the quality of their management.

We study the timing and significance of dividend initiations in the life cycle of a firm. Following a sample of firms from the IPO onwards, and using a hazard model to examine which factors predict initiations, we find that: (i) initiators are large firms with relatively high profitability and cash balances, and low growth rates; and (ii) systematic risk does not change significantly around initiations, in contrast to previous studies on dividend changes. These results are contrary to the signaling theories of dividend policy. Finally, we find mixed evidence that a firm's propensity to initiate dividends is affected by the market sentiment for dividends.

We study the issue of project choice when a risk-averse agent must choose whether to invest in two projects of the same type (focus) or of different types (diversification). Projects of the same type are subject to common type-specific shocks. Hence focusing is more risky within each period, but enables faster learning across periods. Optimal project choice involves balancing these two considerations. We demonstrate how an agent's choice of whether to focus or diversify is related to (i) the speed of learning, (ii) the relative levels of the different kinds of risk and (iii) his risk-aversion and investment horizon. We show that, contrary to intuition, an increase in the prior uncertainty regarding the technology may lead to a decrease in diversification. Our theory is applicable to occupational choice within households, project choice under group lending, and corporate diversification.

We examine the relative importance of the three commonly cited motives for repricing stock options - restoring lost incentives and preventing turnover, as claimed by firms, and recouping lost portfolio wealth, as claimed by critics. Unlike earlier work, we focus on the anticipated turnover prior to a repricing. We first estimate the firm-level turnover propensity and then test whether this measure affects repricing. We find that the threat of executive turnover is the primary factor inducing repricing, while recouping lost wealth plays a secondary role. Incentives do not play a significant role in repricing.

We examine the relationship between the optimal incentive contract and the firm’s decision to fire a manager for poor performance. We first derive some theoretical results using a simple principal-agent model, and then examine the empirical evidence on the incidence of forced turnover among CEOs with different compensation contracts. We find that CEOs with steeper compensation contracts (i.e., with greater incentives) are more likely to be fired following poor firm performance. Logit estimations indicate that among firms that make a net loss in a given year, a CEO receiving incentives at the 60th percentile level is 26.55% more likely to be fired than a CEO with incentives at the 40th percentile. The corresponding figure for firms whose ROA is below the industry average level is 15.07%, and for firms whose stock return is below the market return is 15.86%. The results are robust to various performance and incentive measures. Overall, our re-sults indicate that CEOs with greater incentives also face greater performance pressures.