Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Health resource utilization of labor induction versus expectant management

BACKGROUND

Although induction of labor of low-risk nulliparous women at 39 weeks reduces the risk of cesarean delivery compared with expectant management, concern regarding more frequent use of labor induction remains, given that this intervention historically has been thought to incur greater resource utilization.

OBJECTIVE

The objective of the study was to determine whether planned elective labor induction at 39 weeks among low-risk nulliparous women, compared with expectant management, was associated with differences in health care resource utilization from the time of randomization through 8 weeks postpartum.

STUDY DESIGN

This is a planned secondary analysis of a multicenter randomized trial in which low-risk nulliparous women were assigned to induction of labor at 39 weeks or expectant management. We assessed resource utilization after randomization in 3 time periods: antepartum, delivery admission, and discharge through 8 weeks postpartum.

RESULTS

Of 6096 women with data available, those in the induction of labor group (n = 3059) were significantly less likely in the antepartum period after randomization to have at least 1 ambulatory visit for routine prenatal care (32.4% vs 68.4%), unanticipated care (0.5% vs 2.6%), or urgent care (16.2% vs 44.3%), or at least 1 antepartum hospitalization (0.8% vs 2.2%, P < .001 for all). They also had fewer tests (eg, sonograms, blood tests) and treatments (eg, antibiotics, intravenous hydration) prior to delivery. During the delivery admission, women in the induction of labor group spent a longer time in labor and delivery (median, 0.83 vs 0.57 days), but both women (P = .002) and their neonates (P < .001) had shorter postpartum stays. Women and neonates in both groups had similar frequencies of postpartum urgent care and hospital readmissions (P > .05 for all).

CONCLUSION

Women randomized to induction of labor had longer durations in labor and delivery but significantly fewer antepartum visits, tests, and treatments and shorter maternal and neonatal hospital durations after delivery. These results demonstrate that the health outcome advantages associated with induction of labor are gained without incurring uniformly greater health care resource use.

Trends in diagnoses after implementation of the Chicago classification for esophageal motility disorders (V3.0) for high-resolution manometry studies

To determine trends in the diagnostic distribution of esophageal motility disorders after implementation of the Chicago Classification Version 3.0 (CC V3.0) for interpretation of high-resolution manometry (HRM) studies compared to non-Chicago Classification criteria. Retrospective trends analysis of patients with an HRM study conducted at a single center from January 1, 2013 to September 30, 2015. The implementation of the CC V3.0 for manometry interpretation occurred in September 2014. Patient charts were manually reviewed for data collection including demographics and HRM diagnoses. The prevalence and relative risks (RR) of CC V3.0 diagnostic categories (i.e. normal, indeterminate, achalasia, and EGJ outflow obstruction [EJGOO], and major and minor motility disorders) were calculated before and after CC V3.0 implementation. Four hundred sixty-five HRM studies were included in the study including 268 before and 179 after CC V3.0 implementation. The mean ± SD age was 54 ± 15.4 years and 59.8% were female (n = 278). The percentage with indeterminate diagnosis decreased from 35.3% before CC V3.0 implementation to 16.8% after implementation (adjusted RR 0.5, 95%CI 0.30-0.70, p < 0.001). The percentage with a major motility disorders decreased from 13.9% to 7.3% (adjusted RR 0.5, 95%CI 0.2-1.0, p < 0.001). The percentage with EJGOO and minor diagnoses increased from 1.4% to 14.5% and 11.9% to 22.9%, respectively. The percentage with achalasia and normal diagnosis did not change over the study period. Implementation of CCV3.0 was associated with changes in the distribution of esophageal motility diagnoses in clinical practice. The percentage of indeterminate and major diagnosis decreased and EGJOO and minor diagnoses increased. The decrease in the number of indeterminate studies suggests that the CC V3.0 may clarify the criteria for the interpreting physician. The increase in studies with a diagnosis of EGJ outflow obstruction may reflect the heterogeneity of disorders with clinically relevant outflow obstruction.

Effects of Compression Hosiery in Female Workers with a Standing Profession

Objective:

To evaluate the effect of compression hosiery during standing work.

Design:

An open study, comparing symptoms and plethysmographic findings before and after treatment.

Setting:

University hospital, vascular surgery.

Subjects:

Forty-eight female volunteers with a standing profession.

Methods:

Visual analogue scale to evaluate symptoms and foot volumetry to study venous function before and after 4 weeks use of compression hosiery (20–30 mmHg).

Result:

All scores for symptoms were significantly reduced after treatment. Only 21% of the study subjects had minor abnormalities on foot volumetry. The expelled volume was significantly higher after work at 4 weeks than at the first measurement at inclusion, while the refilling rate was significantly lower after work at 4 weeks than at the corresponding measurement at inclusion.

Conclusion:

Symptomatic improvement was recorded after compression treatment. Limited effects were seen with the objective measurement, although the most important factor, the refilling rate, diminished significantly during the treatment period. Compression treatment reduces lower limb symptoms following standing work.

A multi-method review of home-based chemotherapy

This study summarises research- and practice-based evidence on home-based chemotherapy, and explores existing delivery models. A three-pronged investigation was conducted consisting of a literature review and synthesis of 54 papers, a review of seven home-based chemotherapy programmes spanning four countries, and two case studies within the Canadian province of Ontario. The results support the provision of home-based chemotherapy as a safe and patient-centred alternative to hospital- and outpatient-based service. This paper consolidates information on home-based chemotherapy programmes including services and drugs offered, patient eligibility criteria, patient views and experiences, delivery structures and processes, and common challenges. Fourteen recommendations are also provided for improving the delivery of chemotherapy in patients' homes by prioritising patient-centredness, provider training and teamwork, safety and quality of care, and programme management. The results of this study can be used to inform the development of an evidence-informed model for the delivery of chemotherapy and related care, such as symptom management, in patients' homes.

The role of SARM1 in Toll-like receptor and viral-induced neuronal apoptosis (INM7P.347)

Neuronal apoptosis is a key aspect of several neurological diseases but the mechanisms leading to apoptosis are not well understood. Recent studies have suggested that activation of Pattern Recognition Receptors (PRRs) of neurons leads to neuronal apoptosis, even in the absence of pathogen insult. For example, combined stimulation of neurons through toll-like receptors (TLRs) TLR7 and TLR9 results in significant apoptosis. Using neurons from transgenic mice, we found that TLR-induced apoptosis required endosomal localization of TLRs but was independent of MyD88 signaling. Instead, apoptosis required sterile alpha armadillo motif (SARM1), which localized to the mitochondria following TLR activation and was associated with mitochondrial accumulation in neurites. Deficiency in SARM1 inhibited both mitochondrial accumulation and TLR-induced apoptosis. These studies indicate a previously unknown pathway for TLR-mediated neuronal apoptosis and provide a mechanism for how innate immune responses in the CNS directly induce neuronal damage. SARM1 also induces neuronal apoptosis in a Bunyavirus infection model through another PRR pathway, suggesting that SARM1 may be a common mechanism for innate-immune driven neuronal apoptosis. Our current studies are focused on understanding the interaction of SARM1 with other cellular proteins to identify: 1) the mechanism that regulates SARM1 localization to mitochondria, and 2) the mechanism by which SARM1 influences mitochondrial trafficking.

Innate immune-induced neuronal cell apoptosis via a SARM1 mediated mechanism in the absence of viral replication. (INM9P.451)

Neuronal cell death is a hallmark of multiple neurological diseases including viral infections. The innate immune response in the CNS can contribute to neuronal cell death indirectly through the production of cytokines and neurotoxins as well as via the recruitment of immune cells. However, the direct induction of neuronal cell death via innate immune mechanisms is less well characterized and often confused by confounding factors such as viral replication. We previously identified sterile alpha and HEAT/Armadillo motif containing 1 (SARM1) as a mediator of bunyavirus induced neuronal apoptosis. Currently, we have identified a new mechanism of SARM1-mediated neuronal cell death independent of viral infection of the cell. Treatment with TLR7 and TLR9 agonists induces significant levels of neuronal cell death in cortical neurons. Cell death was associated with induction of SARM1 and inhibition of SARM1 suppressed TLR7 and TLR9 mediated neuronal apoptosis. SARM1 localized to the mitochondria and induced oxidative damage leading to neuronal apoptosis. Mechanistic studies indicated that SARM1 co-localized with both PINK1 and UXT proteins indicating a putative mechanism of SARM1 mediated neuronal cell. Thus, activation of pattern-recognition receptors on neurons in the absence of active virus infection can lead to neuronal death and the mechanism of death is via production of SARM leading to mitochondrial damage.

Genistein and exercise do not improve cardiovascular risk factors in the ovariectomized rat

OBJECTIVE

To investigate the effect of either genistein, or exercise, or both, on parameters that are indicators of cardiovascular health.

METHODS

We investigated the effect of genistein treatment (300 mg genisten/kg body weight/day), or exercise training, or combined genistein and exercise training, for a period of 6 weeks on physical characteristics, cardiovascular plasma markers, blood pressure, aortic morphology, cardiac structure and oxidative stress in the ovariectomized (OVX) Sprague-Dawley rat. Comparisons were made with intact rats.

RESULTS

Ovariectomy (compared to intact) resulted in significant decreases in uterine weight (6-fold, p < 0.0001), insulin levels (4-fold, p = 0.0214), insulin/glucose ratio (3-fold, p = 0.0029), and tumor necrosis factor-α plasma levels (2-fold, p < 0.0001). Similarly, aortic blood pressure was significantly increased (by 8%, p < 0.0033) in OVX rats, without changes in aortic luminal or wall dimensions. Heart surface area was significantly increased (by 16%, p = 0.0160) in OVX rats and this was without changes in non-protein thiol levels (a marker of oxidative stress). Physical characteristics were not altered by treatment with genistein, or genistein with exercise, with the exception of increased uterine weight in OVX rats treated under these same conditions. There were no effects of genistein or exercise on indices of blood pressure and aortic morphology in the OVX rat. However, right ventricular nuclei count was reduced in sedentary genistein-treated rats compared to non-treated control OVX rats.

CONCLUSION

Our results indicate that administration of genistein at this dose, treadmill running, or the combination of both, are not associated with any improvement in cardiovascular function and structure, and risk factors in an ovariectomy model of postmenopause.

Immunologic characteristics of intrarenal T cells: trafficking of expanded CD8+ T cell β-chain clonotypes in progressive lupus nephritis

OBJECTIVE

To better define the immunologic character of the T cell infiltrate in lupus nephritis.

METHODS

We performed double immunohistochemical staining and clonotypic T cell receptor (TCR) β-chain sequencing in multiple anatomic regions isolated by laser-capture microdissection from renal biopsy samples.

RESULTS

Systemic lupus erythematosus (SLE) kidneys have a variably patterned and often extensive infiltrate of predominantly clonally expanded T cells of CD4 and CD8 lineages. CD4+ T cells were prominent in nearly two-thirds of SLE biopsy samples and were distributed as broad periglomerular aggregates or intermixed with CD8+ T cells forming periglomerular caps. Sequencing of the TCR from periglomerular regions showed a predominance of clonally expanded T cells. The CD8+ T cells, which were present in all biopsy samples, often adhered to Bowman's capsule and infiltrated the tubular epithelium. They exhibited features that suggest participation in an adaptive immune response: differentiation into CD28(null) memory-effector phenotype, trafficking of the same expanded clonotype to different regions of the kidney and to the peripheral blood, and clonal persistence for years in repeat biopsy samples. CD8+ T cell tubulitis was especially associated with progressive changes.

CONCLUSION

The immunologic characteristics of the infiltrating CD4+ and CD8+ T cells in the lupus kidney indicate that they have the potential to mediate injury, which may be relevant to development of progressive renal failure. Whereas the oligoclonality of the CD4+ T cell infiltrate is consistent with the paradigm of SLE as a class II major histocompatibility complex-associated autoimmune disease, the finding of CD8+ T cell clonality and trafficking implies participation in a distinct systemic adaptive immune response.

Innate immune response contributes to virus-mediated neuronal death through activation of SARM (170.2)

Neuronal cell death is a hallmark of various neurological diseases including virus infection. The innate immune response in the CNS contributes to neuronal damage through cytokine and neurotoxin production as well as the recruitment of inflammatory cells. However, the role of the innate immune response in the induction of neuronal death is poorly understood. La Crosse virus (LACV), which is a major cause of pediatric encephalitis in the United States, predominantly infects neurons and is associated with neurodegenerative changes. Infection results in neuronal apoptosis. In the current studies we identified sterile alpha and HEAT/Armadillo motif containing 1 (SARM1) protein, a negative regulator of TLR signaling, as a moderator of LACV induced neuronal apoptosis. SARM 1 was induced in neurons following LACV infection and SARM1 knock down studies in neurons demonstrated increased viability during LACV infection as compared to wild-type controls. Direct TLR stimulation of neurons induced SARM 1 which correlated with neuronal apoptosis. Thus, SARM induced as a response to innate immune activation appears to contribute to neuronal death. We are currently investigating the mechanisms underlying SARM induced neuronal death following LACV infection.

A wing-assisted running robot and implications for avian flight evolution

DASH+Wings is a small hexapedal winged robot that uses flapping wings to increase its locomotion capabilities. To examine the effects of flapping wings, multiple experimental controls for the same locomotor platform are provided by wing removal, by the use of inertially similar lateral spars, and by passive rather than actively flapping wings. We used accelerometers and high-speed cameras to measure the performance of this hybrid robot in both horizontal running and while ascending inclines. To examine consequences of wing flapping for aerial performance, we measured lift and drag forces on the robot at constant airspeeds and body orientations in a wind tunnel; we also determined equilibrium glide performance in free flight. The addition of flapping wings increased the maximum horizontal running speed from 0.68 to 1.29 m s⁻¹, and also increased the maximum incline angle of ascent from 5.6° to 16.9°. Free flight measurements show a decrease of 10.3° in equilibrium glide slope between the flapping and gliding robot. In air, flapping improved the mean lift:drag ratio of the robot compared to gliding at all measured body orientations and airspeeds. Low-amplitude wing flapping thus provides advantages in both cursorial and aerial locomotion. We note that current support for the diverse theories of avian flight origins derive from limited fossil evidence, the adult behavior of extant flying birds, and developmental stages of already volant taxa. By contrast, addition of wings to a cursorial robot allows direct evaluation of the consequences of wing flapping for locomotor performance in both running and flying.

Role of oxidative stress in hypoxia preconditioning of cells transplanted to the myocardium: a molecular imaging study

AIM

Cell-based therapies are a potential therapeutic alternative for the treatment of coronary artery disease (CAD). However, transplanted cells undergo significant death in the living subject. Hypoxic preconditioning (HPC) is a potential intervention to increase transplanted cell survival. However, the biological mechanisms of this benefit remain unclear. We hypothesize that the beneficial effect of HPC on stem cell survival is in part due to preservation of oxidant status, an effect that will be monitored using state-of-the-art molecular imaging.

METHODS

H9c2 rat cardiomyoblasts expressing the construct CMV-firefly luciferase (h9c2-fluc), with and without HPC, were exposed to hypoxia, and oxidative stress and cell survival were measured. Subsequently, H9c2-fluc cells, with and without HPC, were injected into the myocardium of rats and cell survival was monitored daily with Bioluminescence (BLI) using a CCD camera.

RESULTS

Compared to controls, cells exposed to hypoxia had increased amount of reactive oxygen species (ROS, control: 14.1±0.9 vs. hypoxia: 19.5 ± 2.0 RFU/µg protein, P=0.02) and decreased cell survival (control: 0.29 ± 0.005 vs. hypoxia: 0.24 ± 0.005 OD, P<0.001). HPC treatment decreased the amount of hypoxia-induced ROS (HPC: 11.5 ± 0.7RFU/µg protein, P=0.002 vs. hypoxia and P=0.11 vs. control), associated with improved survival (HPC: 0.27 ± 0.004OD/µg protein, P=0.002 vs. hypoxia and P=0.005 vs. control). Most importantly, compared to un-conditioned cells, HPC-cells had increased cell survival after transplantation to the myocardium (C: 34.7 ± 6.7% vs. HPC: 83.4 ± 17.5% at day 5 compared to day 1, P=0.01).

CONCLUSION

The beneficial effect of HPC is in part due to preservation of oxidant status. Molecular imaging can assess changes in cell survival in the living subject and has the potential to be applied clinically.

Literacy, education and adherence to antiretroviral therapy in The Gambia

We examined the relationship of patients' literacy and education to antiretroviral therapy (ART) adherence in an urban treatment centre in The Gambia. Information on education and literacy systematically collected before ART initiation was compared against selected adherence outcomes. Formally educated patients were significantly more likely to achieve virological suppression at both six and 12 months (87% vs. 67%, OR=3.13, P=0.03; 88% vs. 63%, OR=4.49, P=0.007, respectively). Literate patients had similar benefit at 12 months (OR=3.39 P=0.03), with improved virological outcomes associated with degree of literacy (P=0.003). A trend towards similar results was seen at 6 months for Koranically educated patients; however, this was no longer apparent at 12 months. No significant correlation was seen between socio-demographic characteristics and missed appointments. Our study suggests that literacy, formal education and possibly Koranic education may impact favourably on adherence to ART.

A pilot study: sodium urate synovitis as an acute model of inflammatory response using objective and subjective criteria to evaluate arthritic pain in cats

Sodium urate (SU) synovitis was evaluated as a model for feline arthritic pain using a placebo- and positive-controlled (meloxicam) randomized blinded controlled single crossover design. Monosodium urate crystals [20 mg (1 mL) rod-shaped] were injected into alternate stifles of trained anesthetized cats (n = 3) with a 28 day washout. During the first trial phase, two cats received meloxicam (0.1 mg/kg, PO), a nonsteroidal anti-inflammatory drug (NSAID), for three days before and on the day of SU injection; the third cat received placebo. Treatments and stifles were switched for the second trial. Total force, contact pressure and area of the fore and hind limbs were measured using a pressure mat one day and 0.5 h before, and 2, 4, 6, 8, 10, 24, and 30 h post-SU injection. Skin temperature, joint circumference, analgesia, lameness, and visual analogue scale (VAS) pain scores, were measured at the same times. Comparisons were made for each time and for areas under the curve (AUC) using original and change from baseline; P < 0.05 was significant. Significant differences in force mat data and subjective data were found for the hind limb data (total force and total contact pressure at 6, 10, and 30 h; analgesia and VAS for pain at 4 h; lameness at 10, 24, and 30 h) and for AUC(0)-->(24h) and AUC(0)-->(30 h) (total force, total contact pressure, and mean lameness score) and for differences from BL AUC(0)-->(10h) (total contact area) and AUC(0)-->(24h) (total contact area and mean lameness score) and AUC(0)-->(30 h) (total force, total contact area, and mean lameness). No cats required rescue analgesia. Injection of 1 mL of monosodium urate into the stifle of a cat causes moderate transitory pain and was suitable for assessing analgesic efficacy of an NSAID with a pressure mat and subjective criteria.

Relationships between glucose variability and conventional measures of glycemic control in continuously monitored patients with type 2 diabetes

Given the importance of glucose variability in the development of diabetic complications, the present study used continuous glucose monitoring (CGM) to determine various indices of glucose variability and to investigate their relationships with conventional measures of chronic sustained hyperglycemia. We examined 53 women and 61 men, aged 36-79 years afflicted with type 2 diabetes for 1-24 years. The following indices of glycemic variability were computed from CGM data sets: mean amplitude of glycemic excursions (MAGE), CGM glucose range, interquartile range (IQR), SD-score, and average daily risk range (ADRR). CGM measurements and self-monitored blood glucose (SMBG) records were used to calculate mean CGM sensor glucose and mean SMBG, respectively. In simple correlation analysis, the indices of glucose variability showed weak correlations with HbA1c: MAGE (r=0.27, p <0.01), CGM glucose range (r=0.21, p <0.05), IQR (r=0.31, p <0.01), SD-score (r=0.34, p<0.001), and ADRR (r=0.24, p<0.05). These indices were found to differ at identical HbA1c among several patients, as reflected by diurnal excursions of different frequency and magnitude. With the exception of ADRR, stronger correlations were found between mean SMBG and the other variability indices (r=0.51-0.63, p<0.01 for all). CGM provides various indices of glycemic variability not captured by conventional measures of glycemic control. Detection of the location and the magnitude of glucose fluctuations by CGM should aid in optimal treatment of glycemic disorders in type 2 diabetes.

Eosinophilic oesophagitis in patients presenting with dysphagia--a prospective analysis

BACKGROUND

Eosinophilic oesophagitis (EoO) may be a common finding in adults presenting with dysphagia.

AIM

To identify the risk factors and prevalence of EoO in an adult population with dysphagia.

METHODS

All patients with dysphagia referred for an upper endoscopy (EGD) were asked to participate. Patients completed a detailed questionnaire followed by EGD with four quadrant biopsies in the distal and mid-oesophagus. Primary endpoint was the prevalence of EoO; secondary endpoints included age, gender, asthma, food allergies, gastro-oesophageal reflux disease/dysphagia score and endoscopic findings.

RESULTS

Two hundred and sixty-one patients enrolled between December 2005 and January 2007. Thirty-one patients (12%) met pathological criteria for EoO. There was no difference in EoO prevalence within each gender. Mean age of EoO patients was 42 +/- 15 vs. 61 +/- 15 for non-EoO patients (P < 0.001). EoO was diagnosed in 35% of patients <50 years of age. EoO was present in 22% of asthmatics vs. 9% non-asthmatics (P < 0.01). EoO was present in 36.8% of patients with self-reported food allergies vs. 9.3% those without allergy (P < 0.001). A 13/31(42%) of EoO patients did not have the classic EGD findings (rings +/- furrows) and would have been missed without oesophageal biopsies.

CONCLUSIONS

Eosinophilic oesophagitis was diagnosed in 12% of the patients presenting with dysphagia with relative risk of 9.5 if age <50 years. Oesophageal biopsies are warranted in patients presenting with dysphagia especially in the younger population. Patients may not present with classic endoscopic findings and EoO can be missed without biopsies.

Fill-tube-induced mass perturbations on x-ray-driven, ignition-scale, inertial-confinement-fusion capsule shells and the implications for ignition experiments

On the first inertial-confinement-fusion ignition facility, the target capsule will be DT filled through a long, narrow tube inserted into the shell. microg-scale shell perturbations Delta m' arising from multiple, 10-50 microm-diameter, hollow SiO2 tubes on x-ray-driven, ignition-scale, 1-mg capsules have been measured on a subignition device. Simulations compare well with observation, whence it is corroborated that Delta m' arises from early x-ray shadowing by the tube rather than tube mass coupling to the shell, and inferred that 10-20 microm tubes will negligibly affect fusion yield on a full-ignition facility.

Propagating the effects of missing data sources in a surveillance system

Sporadically missing data sources in syndromic surveillance systems result in inaccurate counts and detection algorithm results. We examined how data quality issues relating to missing data sources propagate through a surveillance system and devised a method to track and visualize the resulting data quality issues.

Microscopic and flow cytometric semen assessment of Dutch AI-bucks: Effect of semen processing procedures and their correlation to fertility

This study was done to determine the effects of processing techniques on the quality of semen from Dutch AI-bucks with the view on improving pregnancy rates after artificial insemination (AI) with liquid or frozen-thawed semen. Motility of spermatozoa was estimated under a microscope whereas the percentage live spermatozoa and the percentage live spermatozoa with intact acrosomes were determined by means of flow cytometry. Aspects of semen processing that were investigated are storage temperature of liquid semen (i), the effect of glycerol on liquid-stored semen (ii), removal of seminal plasma (iii) and type of extender (iv). The correlation between semen quality and fertility rates in inseminated does was also investigated. The percentage motile spermatozoa in semen stored in liquid form for 72 h progressively declined over time, irrespective of whether storage occurred at 4 or 18 degrees C. The percentage motile spermatozoa in semen stored at 18 degrees C was similar to that in semen stored at 4 degrees C if stored for 24 h but lower if stored for 48 h. Goats differ in the sensitivity of their spermatozoa to the deleterious effects of glycerol. Neither the removal of seminal plasma nor the type of extender had any effect on semen quality before freezing but semen frozen in a Tris-citric acid-glucose (TCG) buffer with egg yolk without removal of the seminal plasma had better quality after thawing than semen frozen in another diluent or after removal of seminal plasma. Remarkably no significant correlation between fertility and membrane integrity of spermatozoa could be found. Thus, although integrity assays for spermatozoa are useful to asses resistance to semen handling, the validity of these assays for predicting fertility is questioned.

Preschool children's eating behaviours are related to dietary adequacy and body weight

OBJECTIVE

The aim of this paper is to analyse the relationships between eating behaviours (picky eating, irregular eating and overeating), and dietary adequacy in accordance with nutrition recommendations and body weight during the preschool years.

DESIGN AND SETTING

Our analyses were performed using data from the Longitudinal Study of Child Development in Québec (1998-2002), a population-based birth cohort.

SUBJECTS

The study followed a representative sample (n=2103) of children born in 1998 in the Canadian province of Québec.

METHODS

Eating behaviours were derived from self-administered questionnaires when children were 2.5, 3.5 and 4.5 years. Nutrition data were collected from one 24-hour recall interview conducted at home by trained nutritionists at 4.5 years. Children's weight and height were measured at 4.5 years. Statistical analyses were carried out with SAS (version 8.2). Weighted data adjusted for within-variability were used in the analysis, and the significance level was set at 5%.

RESULTS

Picky eaters consume fewer total fats, less energy and less protein than children never reporting picky eating behaviours. Picky eaters were more likely to consume less than dietary recommendations for fruit and vegetables, and meat and alternatives. Overeaters consumed more total energy and more of each macronutrient than children who were never reported as overeaters during the preschool years. These children consumed more servings of grain products and meats and alternatives per day than children not classified as overeaters. Even when the number of servings of grain products consumed was similar for overeaters and children who were never overeaters, overeaters had higher body mass index.

CONCLUSION

Given that children as young as 4.5 years are displaying some form of problematic eating behaviour which is shown to be related to dietary adequacy and body weight, public health professionals should be targeting parents of young children to provide messages about strategies for coping with problematic eating behaviours in early childhood.

In vivo interactions of ecotropic and polytropic murine leukemia viruses in mixed retrovirus infections

Mixed retrovirus infections are the rule rather than the exception in mice and other species, including humans. Interactions of retroviruses in mixed infections and their effects on disease induction are poorly understood. Upon infection of mice, ecotropic retroviruses recombine with endogenous proviruses to generate polytropic viruses that utilize different cellular receptors. Interactions among the retroviruses of this mixed infection facilitate disease induction. Using mice infected with defined mixtures of the ecotropic Friend murine leukemia virus (F-MuLV) and different polytropic viruses, we demonstrate several dramatic effects of mixed infections. Remarkably, inoculation of F-MuLV with polytropic MuLVs completely suppressed the generation of new recombinant viruses and dramatically altered disease induction. Co-inoculation of F-MuLV with one polytropic virus significantly lengthened survival times, while inoculation with another polytropic MuLV induced a rapid and severe neurological disease. In both instances, the level of the polytropic MuLV was increased 100- to 1,000-fold, whereas the ecotropic MuLV level remained unchanged. Surprisingly, nearly all of the polytropic MuLV genomes were packaged within F-MuLV virions (pseudotyped) very soon after infection. At this time, only a fractional percentage of cells in the mouse were infected by either virus, indicating that the co-inoculated viruses had infected the same small subpopulation of susceptible cells. The profound amplification of polytropic MuLVs in coinfected mice may be facilitated by pseudotyping or, alternatively, by transactivation of the polytropic virus in the coinfected cells. This study illustrates the complexity of the interactions between components of mixed retrovirus infections and the dramatic effects of these interactions on disease processes.

Is there a correlation between age and D-aspartic acid in human knee cartilage?

L-Aspartic acid (L-Asp) is one of the fastest racemizing amino acids such that the abnormal D-form (D-Asp) has been found in stable biological human tissues such as dentin in teeth, eye lens and brain. Earlier reports showed that there was a linear correlation between age and D-Asp in teeth. We have previously reported that significant levels of D-Asp were found in normal and osteoarthritic knee cartilage. Since cartilage is a slow regenerating tissue, we hypothesized that D-Asp should accumulate in knee cartilage and that there might be a correlation between the age of the person and the amount of D-Asp found in cartilage. Our analysis of approximately 100 samples of normal knee cartilage showed that there are detectable amounts of D-Asp (2-4% of total Asp) in knee cartilage. However, there was only a slight correlation (r = 0.35) between the age of the person and the amount of D-Asp (nmoles/g). Surprisingly, there was a better correlation between age and the amount of D-Asp in the male subjects (r = 0.57) than in the female subjects (r = 0.21).

Reducing workload in systematic review preparation using automated citation classification

OBJECTIVE

To determine whether automated classification of document citations can be useful in reducing the time spent by experts reviewing journal articles for inclusion in updating systematic reviews of drug class efficacy for treatment of disease.

DESIGN

A test collection was built using the annotated reference files from 15 systematic drug class reviews. A voting perceptron-based automated citation classification system was constructed to classify each article as containing high-quality, drug class-specific evidence or not. Cross-validation experiments were performed to evaluate performance.

MEASUREMENTS

Precision, recall, and F-measure were evaluated at a range of sample weightings. Work saved over sampling at 95% recall was used as the measure of value to the review process.

RESULTS

A reduction in the number of articles needing manual review was found for 11 of the 15 drug review topics studied. For three of the topics, the reduction was 50% or greater.

CONCLUSION

Automated document citation classification could be a useful tool in maintaining systematic reviews of the efficacy of drug therapy. Further work is needed to refine the classification system and determine the best manner to integrate the system into the production of systematic reviews.