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Insecticide-based interventions have contributed to ∼78% of the reduction in the malaria burden in sub-Saharan Africa since 2000. Insecticide resistance in malaria vectors could presage a catastrophic rebound in disease incidence and mortality. A major impediment to the implementation of insecticide resistance management strategies is that evidence of the impact of resistance on malaria disease burden is limited. A cluster randomized trial was conducted in Sudan with pyrethroid-resistant and carbamate-susceptible malaria vectors. Clusters were randomly allocated to receive either long-lasting insecticidal nets (LLINs) alone or LLINs in combination with indoor residual spraying (IRS) with a pyrethroid (deltamethrin) insecticide in the first year and a carbamate (bendiocarb) insecticide in the two subsequent years. Malaria incidence was monitored for 3 y through active case detection in cohorts of children aged 1 to

Background The cornerstone of current schistosomiasis control programmes is delivery of praziquantel to at-risk populations. Such preventive chemotherapy requires accurate information on the geographic distribution of infection, yet the performance of alternative survey designs for estimating prevalence and converting this into treatment decisions has not been thoroughly evaluated. Methodology/Principal findings We used baseline schistosomiasis mapping surveys from three countries (Malawi, Côte d’Ivoire and Liberia) to generate spatially realistic gold standard datasets, against which we tested alternative two-stage cluster survey designs. We assessed how sampling different numbers of schools per district (2–20) and children per school (10–50) influences the accuracy of prevalence estimates and treatment class assignment, and we compared survey cost-efficiency using data from Malawi. Due to the focal nature of schistosomiasis, up to 53% simulated surveys involving 2–5 schools per district failed to detect schistosomiasis in low endemicity areas (1–10% prevalence). Increasing the number of schools surveyed per district improved treatment class assignment far more than increasing the number of children sampled per school. For Malawi, surveys of 15 schools per district and 20–30 children per school reliably detected endemic schistosomiasis and maximised cost-efficiency. In sensitivity analyses where treatment costs and the country considered were varied, optimal survey size was remarkably consistent, with cost-efficiency maximised at 15–20 schools per district. Conclusions/Significance Among two-stage cluster surveys for schistosomiasis, our simulations indicated that surveying 15–20 schools per district and 20–30 children per school optimised cost-efficiency and minimised the risk of under-treatment, with surveys involving more schools of greater cost-efficiency as treatment costs rose., Author summary Many countries are currently scaling up efforts to control schistosomiasis, a helminthic disease for which preventive chemotherapy with praziquantel is the main control tool. In order to apply WHO guidelines on how frequently to treat a given district or similar geographic unit for schistosomiasis, survey-based estimates of infection prevalence are required. However, the optimal size and design of survey for generating such data is not clear, and there is a clear trade-off between accuracy and cost–larger surveys provide more accurate information with which to target treatment, but cost more to carry out. Here, we systematically assess what size and design of simple 2-stage cluster survey (where primary school children are tested for infection), might best enable control programmes to implement WHO treatment guidelines. We use empirical data on schistosomiasis distribution from three African countries together with computer simulations to compare survey performance, in terms of accuracy and cost-efficiency–the ability of a survey to accurately determine treatment frequency, per unit cost. We show that although small surveys of around 5 schools per district are frequently adopted for mapping schistosomiasis, such small surveys are prone to miss endemic schistosomiasis fairly often, and are also not cost efficient. Our results suggest that among the designs tested, surveys involving 15–20 schools per district optimise cost-efficiency, providing the most accurate treatment decisions per dollar spent. These findings have important implications for the schistosomiasis control community, and provide the first evidence-based suggestion of a simple survey design for mapping schistosomiasis in endemic countries.

It is widely known that the recent Ebola Virus Disease (EVD) in West Africa caused a serious disruption to the national health system, with many of ongoing disease focused programmes, such as mass drug administration (MDA) for onchocerciasis (ONC), lymphatic filariasis (LF) and schistosomiasis (SCH), being suspended or scaled-down. As these MDA programmes attempt to restart post-EVD it is important to understand the challenges that may be encountered. This commentary addresses the opinions of the major health sectors involved, as well as those of community members, regarding logistic needs and challenges faced as these important public health programmes consider restarting. There appears to be a strong desire by the communities to resume NTD programme activities, although it is clear that some important challenges remain, the most prominent being those resulting from the severe loss of trained staff. Electronic supplementary material The online version of this article (doi:10.1186/s40249-017-0272-8) contains supplementary material, which is available to authorized users.

Background Loiasis is a filarial disease caused Loa loa. The main vectors are Chrysops silacea and C. dimidiata which are confined to the tropical rainforests of Central and West Africa. Loiasis is a mild disease, but individuals with high microfilaria loads may suffer from severe adverse events if treated with ivermectin during mass drug administration campaigns for the elimination of lymphatic filariasis and onchocerciasis. This poses significant challenges for elimination programmes and alternative interventions are required in L. loa co-endemic areas. The control of Chrysops has not been considered as a viable cost-effective intervention; we reviewed the current knowledge of Chrysops vectors to assess the potential for control as well as identified areas for future research. Results We identified 89 primary published documents on the two main L. loa vectors C. silacea and C dimidiata. These were collated into a database summarising the publication, field and laboratory procedures, species distributions, ecology, habitats and methods of vector control. The majority of articles were from the 1950–1960s. Field studies conducted in Cameroon, Democratic Republic of Congo, Equatorial Guinea, Nigeria and Sudan highlighted that C. silacea is the most important and widespread vector. This species breeds in muddy streams or swampy areas of forests or plantations, descends from forest canopies to feed on humans during the day, is more readily adapted to human dwellings and attracted to wood fires. Main vector targeted measures proposed to impact on L. loa transmission included personal repellents, household screening, indoor residual spraying, community-based environmental management, adulticiding and larviciding. Conclusions This is the first comprehensive review of the major L. loa vectors for several decades. It highlights key vector transmission characteristics that may be targeted for vector control providing insights into the potential for integrated vector management, with multiple diseases being targeted simultaneously, with shared human and financial resources and multiple impact. Integrated vector management programmes for filarial infections, especially in low transmission areas of onchocerciasis, require innovative approaches and alternative strategies if the elimination targets established by the World Health Organization are to be achieved. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-2103-y) contains supplementary material, which is available to authorized users.

Free-ranging Red-eared Sliders (Trachemys scripta elegans) were captured from farm ponds located in the Flint Hills of Kansas and a zoo pond in Emporia, Kansas, USA, to evaluate their enteric bacterial flora and associated antibiotic resistance. Bacteria obtained from cloacal swabs were composed of six different Gram-negative genera. Although antibiotic resistance was present in turtles captured from both locations, 40 and 49% of bacteria demonstrated multiple antibiotic resistance to four of the antibiotics tested from the zoo captured and Flint Hills ponds turtles, respectively. These data illustrate environmental antibiotic resistance is widespread in the bacterial flora obtained from Red-eared Sliders in east central Kansas.

Ponds are common in many agricultural landscapes and provide aquatic habitat for wildlife. Most studies of semi-aquatic turtle assemblages have been conducted in lotic environments or large lentic habitats (e.g., lakes, reservoirs), but few studies have described pond communities. We used Frame nets and basking traps to sample turtle assemblages within eight ponds located in east-central Kansas (Lyon Co.) from 15 May 2007 – 1 October 2007. Our objective was to describe selected aspects of the semi-aquatic turtle assemblages in these ponds: species richness, relative abundance, catch per unit effort, and density. A total of 655 unique individuals were captured and four species were detected (Chrysemys picta bellii, N = 387; Trachemys scripta elegans, N= 188; Chelydra serpentina, N = 79; Pseudemys concinna, N = 1). Chrysemys picta bellii was usually the most abundant species, with T. s. elegans and C. serpentina ranked second and third, respectively. Likewise, catch per unit effort (an index of abundance) w...

The general paradigm associated with overland movements of semi-aquatic turtles between aquatic habitats predicts that males move more frequently and for greater distances than females and juveniles, and that larger individuals move more frequently than smaller individuals. We used capture-mark-recapture techniques to examine interpond movement patterns of western painted turtles (Chrysemys picta) among a complex of eight ponds in east-central Kansas in 2007. We assessed the broad applicability of predictions of the general paradigm by testing the following hypotheses: 1) males make interpond movements more frequently than females, 2) larger adult-sized individuals make interpond movements more frequently than juveniles, 3) propensity for pond-to-pond movement varies as a function of size within categories (i.e., males, females, and juveniles), and 4) mean minimum distance traveled between ponds is greatest for males. The proportion of males that moved between ponds was not significantly different from that of females, and we did not observe a significant difference in proportion of adults and juveniles categorized as movers. Mean length of plastron of individuals classified as movers and non-movers was not significantly different within either females or juveniles. Males categorized as non-movers were significantly larger than those that made interpond movements. Mean minimum distance traveled between ponds was not significantly different among males, females, and juveniles. Thus, our results were not consistent with any of the predictions of the general paradigm. Costs and benefits associated with overland movements of turtles are likely to vary both spatially and temporally. We suggest that as cost-benefit ratios vary, so should predictions about the propensity for interpond movements among turtles of different sexes, sizes, and ontogenetic stages.

Cytochrome c oxidase is the terminal electron acceptor in the electron transport chain in many aerobic organisms. This multi-protein complex can be composed of a varying number of subunits depending on species. In the budding yeast, Saccharomyces cerevisiae, cytochrome c oxidase is made up of 11 subunits, 8 are derived from the nuclear genome and 3 are derived from the mitochondrial genome. To ensure these subunits come together at the correct time and place a family of assembly factors is required. In the case of the mitochondrial DNA encoded subunit 1 there is a linear pathway of biosynthesis where these assembly factors and other structural subunits associate at specific times to regulate specific maturation events. In the absence of some assembly factors subunit 1 is subject to degradation by the protease Oma1p. In yeast, this results in a deficiency in cytochrome c oxidase activity and the inability to grow using substrates requiring intact oxidative phosphorylation. We have performed a mutagenic screen of mitochondrial DNA to identify mutations in the subunit 1 gene that can suppress the oxidative phosphorylation deficient phenotype caused by the absence of the assembly factors, COA2 and SHY1. Through analysis of the COX1 gene we will identify putative regions required for the proteolytic processing of subunit 1 by the Oma1p protease. The information gathered from this research will guide us in identifying putative regions required for cytochrome c oxidase subunit 1 degradation and also provide more information regarding the proteolytic requirements of the Oma1p protease.

Background The prevalence of Wuchereria bancrofti, which causes lymphatic filariasis (LF) in The Gambia was among the highest in Africa in the 1950s. However, surveys conducted in 1975 and 1976 revealed a dramatic decline in LF endemicity in the absence of mass drug administration (MDA). The decline in prevalence was partly attributed to a significant reduction in mosquito density through the widespread use of insecticidal nets. Based on findings elsewhere that vector control alone can interrupt LF, we asked the question in 2013 whether the rapid scale up in the use of insecticidal nets in The Gambia had interrupted LF transmission. Methodology/Principal Finding We present here the results of three independently designed filariasis surveys conducted over a period of 17 years (1997–2013), and involving over 6000 subjects in 21 districts across all administrative divisions in The Gambia. An immunochromatographic (ICT) test was used to detect W. bancrofti antigen during all three surveys. In 2001, tests performed on stored samples collected between 1997 and 2000, in three divisions, failed to show positive individuals from two divisions that were previously highly endemic for LF, suggesting a decline towards extinction in some areas. Results of the second survey conducted in 2003 showed that LF was no longer endemic in 16 of 21 districts surveyed. The 2013 survey used a WHO recommended LF transmission verification tool involving 3180 6–7 year-olds attending 60 schools across the country. We demonstrated that transmission of W. bancrofti has been interrupted in all 21 districts. Conclusions We conclude that LF transmission may have been interrupted in The Gambia through the extensive use of insecticidal nets for malaria control for decades. The growing evidence for the impact of malaria vector control activities on parasite transmission has been endorsed by WHO through a position statement in 2011 on integrated vector management to control malaria and LF., Author Summary The prevalence of lymphatic filariasis (LF), in The Gambia was among the highest in Africa in the 1950s when about 50% of the adult population was positive for microfilaraemia. However, surveys conducted in 1975 and 1976 revealed a dramatic decline in LF endemicity in the absence of systematic treatment with anti-filaria medicines. This decline in LF prevalence in all villages was partly attributed to a significant drop in human-mosquito contact through a sustained reduction in rainfall in the 1960s and 1970s and the widespread use of insecticidal nets to protect against malaria. We asked the question in 2013 whether the rapid scale up in the use of insecticidal nets for malaria control in Gambia had resulted in the interruption of LF transmission. In this paper we present the results of three independently designed filariasis surveys conducted over a period of 17 years (1997–2013), and involving over 6000 subjects in 21 districts across all administrative divisions in the country. In 2001, tests performed to detect circulating filarial antigens (CFA) in serum samples collected between 1997 and 2000, in three divisions, failed to show positive individuals from two that were previously highly endemic for the LF. Results of the second survey conducted in 2003 indicated that five of the 21 districts were slightly endemic for LF with CFA rates of 1% or 2% but MDA was never implemented in The Gambia. The results of our final survey conducted in 2013 were unequivocal in confirming the absence of transmission of LF in all 21 districts surveyed using WHO recommended statistically robust and validated tool known as transmission assessment survey (TAS). The Gambia achieving a non-endemic status for LF represents a significant step in the efforts to shrink the filariasis endemicity map and demonstrates the value of cross sector approaches in disease control.

A common assumption is that titillation by adult female Trachemys scripta (Slider Turtles) always represents female participation in courtship, but there is only limited empirical support for this assertion and some data may contradict this supposition. Behavioral interactions were staged among wild-caught T. scripta throughout the local season of activity for this species (April–October). Each of 47 trials involved 6 turtles (total = 282 turtles: 94 melanistic males, 94 nonmelanistic males, 94 females) videotaped for 3 h (total = 141 h). During our study, titillation behaviors initiated by females were largely intrasexual, exhibited no peak during the local mating period, and did not stimulate males to attempt copulation. We concluded that such characteristics were inconsistent with the traditional assumption of a courtship function and were more consistent with the characteristics of agonistic signals, signals that communicate sender identity, or compound signals with multiple communicative fun...

The effects of stream size and flow regime on spatial and temporal variability of stream fish distribution, abundance, and diversity patterns were investigated. Assemblage variability and species richness were each significantly associated with a complex environmental gradient contrasting smaller, hydrologically variable stream localities with larger localities characterized by more stable flow regimes. Assemblages showing the least variability were the most species-rich and occurred in relatively large, stable environments. Theory suggests that species richness can be an important determinant of assemblage variability. Although this appears to be true in our system, we suggest that spatial and temporal heterogeneity in the environment largely determines both assemblage richness and variability, providing a more parsimonious explanation for the diversity–variability correlation. Changes in species richness of local assemblages across time were coordinated across the landscape, and assemblages formed spatially and temporally nested subset patterns. These results suggest an important link between local community dynamics and community-wide occurrence. At the species level, mean local persistence was significantly associated with regional occurrence. Thus, the more widespread a species was, the greater its local persistence. Our results illustrate how the integrity of local stream fish assemblages is dependent on local environmental conditions, regional patterns of species distribution, and landscape continuity.

Very low in situ permeability gas reservoirs (Kgas

Intrasexual variation in courtship behavior is common but the potential for such variation within turtles has not been considered. Forty-seven behavioral trials with wild-captured slider turtles (Trachemys scripta) were conducted throughout the local season of activity for this species (April–October). The frequency of occurrence, seasonality, and directionality of courtship behaviors (i.e., biting, chasing, and titillation) performed by melanistic and nonmelanistic males were examined. I tested the hypotheses that the expression of these behaviors during the mating season (late August to mid-October) would differ between melanistic and nonmelanistic male T. scripta and that melanistic and nonmelanistic males would differ with respect to their precopulatory display rates. Biting, chasing, and titillation directed toward females by melanistic and nonmelanistic male T. scripta during the mating season were significantly different. Courtship behaviors (i.e., precopulatory displays) were not always p...

Background Lymphatic filariasis (LF) is targeted for elimination through annual mass drug administration (MDA) for 4–6 years. In 2006, Zanzibar stopped MDA against LF after five rounds of MDA revealed no microfilaraemic individuals during surveys at selected sentinel sites. We asked the question if LF transmission was truly interrupted in 2006 when MDA was stopped. Methodology/Principal Findings In line with ongoing efforts to shrink the LF map, we performed the WHO recommended transmission assessment surveys (TAS) in January 2012 to verify the absence of LF transmission on the main Zanzibar islands of Unguja and Pemba. Altogether, 3275 children were tested on both islands and 89 were found to be CFA positive; 70 in Pemba and 19 in Unguja. The distribution of schools with positive children was heterogeneous with pronounced spatial variation on both islands. Based on the calculated TAS cut-offs of 18 and 20 CFA positive children for Pemba and Unguja respectively, we demonstrated that transmission was still ongoing in Pemba where the cut-off was exceeded. Conclusions Our findings indicated ongoing transmission of LF on Pemba in 2012. Moreover, we presented evidence from previous studies that LF transmission was also active on Unguja shortly after stopping MDA in 2006. Based on these observations the government of Zanzibar decided to resume MDA against LF on both islands in 2013., Author Summary Lymphatic filariasis was highly endemic in Zanzibar when MDA commenced in 2001 to eliminate the disease. In 2006, Zanzibar, in the United Republic of Tanzania, was the first territory in Africa to complete five rounds of annual treatment using a combination of albendazole and ivermectin at 100% geographic coverage and achieving effective treatment coverage of over 65% during each round. MDA was stopped in 2006 after sentinel site surveys revealed parasite infection rates of zero in both humans and mosquito populations. In 2012, when new tools became available to verify the absence of transmission, we asked the question if transmission was truly interrupted when MDA was stopped in 2006. In January 2012, we performed the WHO recommended transmission assessment surveys (TAS) on the main islands of Unguja and Pemba to verify the absence of LF transmission in line with ongoing efforts to shrink the LF risk map. Altogether, 3275 children were tested on both islands and 89 were found to be CFA positive; 70 in Pemba and 19 in Unguja. The distribution of schools with positive children was heterogeneous with pronounced spatial variation on both islands. Based on the calculated TAS cut-offs of 18 and 20 CFA positive children for Pemba and Unguja respectively, we demonstrated that transmission was still ongoing in Pemba where the cut-off value was exceeded. We also presented evidence from previous entomological studies that LF transmission was active on Unguja shortly after stopping MDA in 2006. Based on these findings we concluded that LF transmission was still active in Zanzibar, and one million people at risk of acquiring LF, and recommended the resumption of MDA on both islands to eliminate the disease. In 2013, the government of Zanzibar decided to resume MDA with ivermectin plus albendazole on both islands.

El modelo PEAR (“Actividades Agradables-Restricción Conductual”) ha sido propuesto como una manera de entender los efectos del ocio sobre el malestar de cuidadores de personas con demencia. En base al modelo PEAR y al de estrés y afrontamiento, el objetivo de este estudio fue analizar de forma conjunta el papel de la frecuencia y la satisfacción con la activación conductual en la explicación del malestar del cuidador (depresión, ansiedad, salud percibida), el riesgo de institucionalización de la persona cuidada, los estresores y recursos del cuidador (rumiación y reevaluación cognitiva) en una muestra de 275 cuidadores. Método: Se dividió a la muestra en cuatro grupos en función de sus niveles en la frecuencia y la satisfacción con la activación conductual: BFBS = Baja frecuencia + baja satisfacción; BFAS = Baja frecuencia + alta satisfacción; AFBS = Alta frecuencia + baja satisfacción; y AFAS = Alta frecuencia + alta satisfacción. Resultados: Mientras que los cuidadores del grupo AFAS mostraron un perfil más positivo en variables relacionadas con los recursos y de salud, y menores puntuaciones en riesgo de institucionalización en comparación con el resto de los grupos, los cuidadores del grupo BFBS utilizaron en mayor medida estrategias de regulación emocional desadaptativas y mostraron peores consecuencias sobre variables de resultado de salud. Discusión: Los resultados sugieren la importancia de considerar el perfil de frecuencia y satisfacción con el ocio a la hora de entender el malestar del cuidador, The PEAR (pleasant events-activity restriction) model has been proposed as a way of understanding leisure effects on dementia caregivers‟ distress. Considering both the PEAR model and the stress and coping model, the purpose of this study was to analyze the potential of both frequency and satisfaction with leisure to explain caregivers‟ distress (depression, anxiety and perceived health), risk of institutionalization of the care recipient, caregivers‟ stressors and resources variables (rumination and cognitive reappraisal) in 275 caregivers. Methods: The sample was divided in four groups based on caregivers‟ scores on frequency and satisfaction with leisure: LFLS = Low frequency + low satisfaction; LFHS = Low frequency and high satisfaction; HFLS = High frequency + low satisfaction; HFHS = High frequency + high satisfaction. Results: Results indicated that while caregivers from the HFHS group showed a generally more positive profile on resources variables, health outcomes and lower levels of risk of institutionalization compared with the other groups, care-givers from the LFLS group used significantly less adaptive emotional regulation strategies and showed worse consequences on health outcomes. Discussion: The results of this study suggest the importance of considering caregivers‟ profile on frequency and satisfaction with leisure in order to understand caregiving distress, The preparation of this article was supported by grants from both the Spanish Ministry of Science and Innova-tion (Grant SEJ2009-8132/PSIC) and the Spanish Ministry of Economy and Competitiveness (Grant PSI2012-31293)

The objective of this study was to explore whether measures of visual and cognitive performance in a safe computerized driving environment were associated with collision involvement and the cost of collisions in a sample of professional motor vehicle operators. One hundred and nine (109) school bus drivers in a large metropolitan area were asked to take a 15-minute interactive computer-based driving assessment. The skills included visual target identification, scanning in four directions, divided-attention, reaction time, steering smoothness, false positive responses, and evasive maneuvers. An overall score validated in previous research summarized each driver’s performance. Each driver’s collision history over the last three years was then compared to the driving assessment scores. Collision data included collision type, frequency, and damage cost associated with each incident. Drivers with collisions (n = 27) were compared to drivers with no collisions (n = 82). Drivers with collisions had significantly lower overall scanning and steering smoothness scores than drivers without collisions. Drivers with collisions also had significantly higher braking and target false-positive scores, indicating disorientation. The total cost of collisions for the lower 40th percentile test scores was $42,261, whereas the cost for the upper 60th percentile was $10,314. The results indicate that drivers who are prone to become disoriented and overwhelmed in a high-demand computerized assessment were more likely to have had collisions on the road. The relationship between collision cost/incidence and test scores suggests that a sufficiently complex and rapidly paced computerized assessment has utility in identifying drivers who would benefit from remedial training.

There are many ways to send humans to Mars. Credible technical reports can be traced to the 1950's. More recently, NASA has funded major studies that depict a broad variety of trajectories, technologies, stay times, and costs. Much of this data is still valid with direct application to today's exploration planning. This paper presents results comparing these studies with particular emphasis on the in-space transportation aspects of the mission. Specifically, comparisons are made on propulsion systems used for getting the crew and mission equipment from Earth orbit to Mars orbit, descending and ascending from the surface, and returning to Earth orbit. Areas of comparison for each of these phases include crew size, mission mass, propellant mass, delta v, specific impulse, transit time, surface stay time, aero-braking, and others. Data is analyzed to demonstrate either strong trends toward particular technologies or diverging solutions.

Underbalanced drilling is used with increasing frequency on a worldwide basis to reduce invasive formation damage effects and drilling problems associated with many horizontal wells in challenging reservoir exploitation situations. When the primary objective of the underbalanced drilling operation is to reduce or eliminate formation damage effects, the importance of maintaining a continuous underbalanced pressure condition during the complete operation is essential in obtaining the maximum benefit with respect to formation damage reduction. The importance of this has been emphasized in previous work, but this paper details some of the specific reservoir design and operational parameters which must be considered to ensure that the underbalanced pressure condition is maintained on a continuous basis. This includes such issues as pipe connection effects, various wellbore geometries, frictional flow and back pressure effects, localized depletion effects, gravity invasion and drainage effects, countercurrent imbibition effects, hole cleaning, bit jetting, and a number of other issues which can affect the ability to maintain a continuously underbalanced condition in a given reservoir situation. Examples of these situations will be presented, along with suggestions in certain operational circumstances which can be utilized to reduce the effect of these problems. What is Underbalanced Drilling? Underbalanced drilling, in its simplest definition, refers to a condition where the net pressure exerted by the circulating drilling fluid in the annular space between the drill string and the formation is less than the effective pore pressure in the formation adjacent to the wellbore. This results in a pressure imbalance situation where the flow of oil, water, or gas (which may be contained within the pore space) is induced into the wellbore and returns to the surface along with the circulating drilling fluid. Ideally, this condition is generated in every portion of the exposed viable reservoir pay during the complete drilling operation, but in some situations, due to circumstances which will be discussed in detail later in this paper, this may not be the case.

A prospective screening program of 11,161 newborns identified twenty-one infants who had postaxial type-B polydactyly (a prevalence of one in 531 live births). Sixteen infants (76 per cent) had bilateral postaxial type-B polydactyly. Eighteen infants (86 per cent) had a family history of the anomaly. The racial prevalence was one in 143 live births of black infants and one in 1339 live births of white infants. The duplicated small fingers were treated in the newborn nursery with suture ligation at the base of the pedicle. One infant had a second procedure to remove a blackened digit that remained firmly attached one month after the initial treatment. No other complications occurred. Fifteen patients (twenty-eight fingers) were reexamined at an average age of twenty months (range, twelve to thirty-seven months). Twelve fingers (43 per cent) had a residual bump, with an average diameter of two millimeters (range, one to six millimeters). Despite the residual bumps, all of the parents were satisfied with the cosmetic result.

War has always had a powerful influence on music. At times it has the ability to motivate composers even more than love, religious belief, or money. Throughout the ages, both war and music about war have changed dramatically. The destructive power of war has reached its ultimate capabilities -- the potential to eliminate all life. As war has become more and more horrible, and has caused unprecedented amounts of needless deaths, the world's view of war has changed completely. This change in attitude toward war is evident also in the development of war music.

Underbalanced drilling has been utilized with increasing frequency to minimize problems associated with invasive formation damage which often greatly reduce the productivity of oil and gas reservoirs, particularly in open hole horizontal well applications. Underbalanceddrilling, when properly designed and executed, minimizes or eliminates problems associated with the invasion of particulate matter into the formation as well as a multitude of other problems such as adverse clay reactions, phase trapping, precipitation and emulsification which can be caused by the invasion of incompatible mud filtrates in an overbalanced condition. In many underbalanceddrilling operations, additional benefits are seen due to a reduction in drilling time, greater rates of penetration, increased bit life, a rapid indication of productive reservoir zones and the potential for dynamic flow testing while drilling. Underbalanced drilling is not a solution to all formation damage problems. Damage due to poorly designed and/or executed underbalanced drilling programs can rival or even greatly exceed that which may occur using a well-designed conventional overbalanced drilling program. Potential downsides and damage mechanisms associated with underbalanced drilling will be discussed. These include: Increased cost and safety concerns.Difficulty in maintaining a continuously underbalanced condition (due to such factors as pipe connections in rotary drilling, bit trips, mud pulsed logging, bit jetting and flushing effects, localized depletion and subsequent repressurization effects, poor knowledge of initial reservoir pressure, multiple zones with differing initial pressures, slug flow and liquid holdup in the vertical section of the wellbore, frictional pressure drop and mechanical problems with surface equipment or gas supply sources).Spontaneous imbibition and countercurrent imbibition effects.Glazing, mashing and cuttings induced damage.Macroporosity gravity induced invasion.Difficulty of application in zones of extreme pressure and permeability.Political/career risk associated with championing a new and potentially risky technology. This paper discusses reservoir parameters required to design an effective underbalanced or overbalanced drilling program, laboratory screening procedures to ascertain the effectiveness of underbalanced drilling in a specific application and presents screening criteria with respect to the types of reservoirs which present good applications for underbalanced drilling technology.