The manipulation of food resources reveals sex-specific trade-offs between parental self-feeding and offspring care

Parent Palestine sunbirds (Nectarinia osea) feed on flower nectar that is not fed to their nestlings. This phenomenon provided a unique opportunity to manipulate self-feeding rates of parent birds independently of the rate at which they feed arthropod prey to their offspring. Based on provisioning models, we predicted that parents would invest more in their young as the energy content of their own food increased. From our earlier work, we also predicted that the levels of sex-specific activities of males and females would differ as the energy content of their food increased. Sunbird pairs with two or three nestlings were provided with feeders containing a low-, medium- or high-concentration sucrose solution. As the sugar concentration increased, the females delivered arthropods at a greater rate to their nestlings, removed proportionally more faecal sacs and spent longer at the nest, while the males increased their mobbing effort. Nestling food intake and body mass, but not tarsus length or bill size, were larger in small broods than in large broods, and increased with increasing feeder sugar concentration. These results imply that increasing the energy content of food consumed by parent sunbirds allows them to increase the rate at which other foods are delivered to their young and to increase other parental care activities as well. The results also add credence to the idea that behavioural decisions reflect life-history trade-offs between parental self-feeding and investment in current young.

Reduction of Cr(VI) and bioaccumulation of chromium by gram positive and gram negative microorganisms not previously exposed to Cr-stress

Resistance to Cr(VI) is usually associated with its cellular exclusion, precluding enrichment techniques for the isolation of organisms accumulating Cr(VI) via bioreduction to insoluble Cr(III). A technique was developed to screen for potential Cr(VI) reduction in approx. 2000 isolates from a coastal environment, based on the non-specific reduction of selenite and tellurite to Se0 and Te0, and reduction of tetrazolium blue to insoluble blue formazan. The most promising strains were further screened in liquid culture, giving three, which were identified by 16S rRNA sequence analysis as Bacillus pumilus, Exiguobacterium aurantiacum and Pseudomonas synxantha, all of which reduced 100 microM Cr(VI) anaerobically, without growth. The respective removal of Cr(VI) was 90% and 80% by B. pumilus and E. aurantiacum after 48 h and 80% and by P. synxantha after 192 h. With the gram positive strains Cr(VI) promoted loss of flagella and, in the case of B. pumilus, lysis of some cells, but Cr was deposited as an exocellular precipitate which was identified as containing Cr and P using energy dispersive X-ray microanalysis (EDAX). This prompted the testing of Citrobacter sp. N14 (subsequently re-assigned by 16S rRNA sequence analysis and biochemical studies as a strain of Serratia) which bioprecipitates metal cation phosphates via enzymatically-liberated phosphate. This strain reduced Cr(VI) at a rate comparable to that of P. synxantha but Cr(III) was not bioprecipitated where La(III) was removed as LaPO4, even though a similar amount of phosphate was produced in the presence of Cr(III). Since B. pumilus removed most of the Cr(VI), with the formation of cell-bound CrPO4 implicated, this suggests that this strain could have future bioprocess potential.

Automatically Training a Problematic Dialogue Predictor for a Spoken Dialogue System

Spoken dialogue systems promise efficient and natural access to a large variety of information sources and services from any phone. However, current spoken dialogue systems are deficient in their strategies for preventing, identifying and repairing problems that arise in the conversation. This paper reports results on automatically training a Problematic Dialogue Predictor to predict problematic human-computer dialogues using a corpus of 4692 dialogues collected with the 'How May I Help You' (SM) spoken dialogue system. The Problematic Dialogue Predictor can be immediately applied to the system's decision of whether to transfer the call to a human customer care agent, or be used as a cue to the system's dialogue manager to modify its behavior to repair problems, and even perhaps, to prevent them. We show that a Problematic Dialogue Predictor using automatically-obtainable features from the first two exchanges in the dialogue can predict problematic dialogues 13.2% more accurately than the baseline.

Increased non-transferrin bound iron in plasma-depleted SAG-M red blood cell units

BACKGROUND AND OBJECTIVES

Non-transferrin bound iron (NTBI) is associated with increased morbidity in a number of transfusion-dependent disease states such as the severe haemoglobinopathies. We hypothesized that this may be related to excess NTBI present in plasma-depleted red blood cell units that are free of clear haemolysis.

MATERIALS AND METHODS

The level of NTBI was determined using the bleomycin assay in samples from 20 stored plasma-depleted red cell units, at approximate 5-day intervals up to day 33 after donation. Forty units of fresh-frozen plasma (FFP) and 40 units of platelet concentrates were used as negative controls, and samples from 12 units of FFP were also serially assessed.

RESULTS

Median [interquartile range (IQR)] NTBI was 0 microm (0-0.35) in samples taken from units 3-10 days after donation. Thereafter, the levels of NTBI increased, becoming significant (median 3.05; IQR: 0.05-6.7 microm) 17-22 days after donation. After 30 days, NTBI was detectable in all red cell units. NTBI was undetectable in platelet concentrates and FFP.

CONCLUSIONS

Increased levels of NTBI become detectable 17-22 days after donation and increase further with storage time. This excess NTBI may promote bacterial infection in iron-loaded individuals.

Diurnal variation in lipoprotein lipase activity

BACKGROUND

We investigated whether variations in lipoprotein lipase activity, a key post-prandial enzyme involved in the removal of circulating dietary triglycerides, could contribute to the previously described nocturnal lipid intolerance.

METHODS

We studied lipoprotein lipase activity in 12 healthy volunteers (five women, seven men) at 11:30 h and 23:30 h on two separate occasions. Subjects consumed a high-fat mixed meal at 07:30 h for the morning study or 19:30 h for the evening study. Then, after a 4-h fast, subjects were given an intravenous bolus of 7,500 U heparin. Blood samples were collected before and 15 min after heparin administration for measurement of lipoprotein lipase, hepatic lipase, triglycerides and non-esterified fatty acids concentrations.

RESULTS

Post-prandial post-heparin lipoprotein lipase activity was greater in the morning than in the evening (16.5 +/- 1.4 versus 14.4 +/- 1.0 micromol oleate/mL/h; P< 0.05). Post-prandial post-heparin hepatic lipase activity was also greater in the morning than in the evening (8.7 +/- 1.5 versus 81 +/- 1.6 micromol oleate/mL/h; P= 0.002). There were no other significant diurnal differences.

CONCLUSION

We report a diurnal variation in post-prandial lipoprotein lipase activity. This is consistent with the notion that decreased nocturnal insulin sensitivity extends to insulin's actions on lipoprotein lipase and provides a possible explanation for nocturnal lipid intolerance.

Reduced vitamin E antioxidant capacity in sickle cell disease is related to transfusion status but not to sickle crisis

In homozygous sickle cell disease (SCD), decreased serum Vitamin E is present. Excessive transfusions may lead to iron overload. We hypothesised a relationship between the two and found that Vitamin E type antioxidant capacity was significantly lower in 30 SCD patients than in 30 age- and sex-matched controls (P < 0.001). Antioxidant capacity was lower in 10 transfused patients compared with 20 non-transfused patients (P < 0.001). Transfusional iron overload in SCD may increase the potential for oxidative damage, and low antioxidant capacity may compound this effect.

Comparison of the effectiveness of inhaler devices in asthma and chronic obstructive airways disease: a systematic review of the literature

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) are common diseases of the airways and lungs that have a major impact on the health of the population. The mainstay of treatment is by inhalation of medication to the site of the disease process. This can be achieved by a number of different device types, which have wide variations in costs to the health service. A number of different inhalation devices are available. The pressurised metered-dose inhaler (pMDI) is the most commonly used and cheapest device, which may also be used in conjunction with a spacer device. Newer chlorofluorocarbons (CFC)-free inhaler devices using hydrofluoroalkanes (HFAs) have also been developed. The drug is dissolved or suspended in the propellant under pressure. When activated, a valve system releases a metered volume of drug and propellant. Other devices include breath-actuated pMDIs (BA-pMDI), such as Autohaler and Easi-Breathe. They incorporate a mechanism activated during inhalation that triggers the metered-dose inhaler. Dry powder inhalers (DPI), such as Turbohaler, Diskhaler, Accuhaler and Rotahaler, are activated by inspiration by the patient. The powdered drug is dispersed into particles by the inspiration. With nebulisers oxygen, compressed air, or ultrasonic power is used to break up solutions or suspensions of medication into droplets for inhalation. The aerosol is administered by mask or by a mouthpiece. There has been no previous systematic review of the evidence of clinical effectiveness and cost-effectiveness of these different inhaler devices.

OBJECTIVES

To review systematically the clinical effectiveness and cost-effectiveness of inhaler devices in asthma and COPD.

METHODS

The different aspects of inhaler devices were separated into the most clinically relevant comparisons. Methods involved systematic searching of electronic databases and bibliographies for randomised controlled trials (RCTs) and systematic reviews. Pharmaceutical companies and experts in the field were contacted for further information. Trials that met the inclusion criteria were appraised and data extraction was under-taken by one reviewer and checked by a second reviewer, with any discrepancies being resolved through agreement. RESULTS--IN VITRO CHARACTERISTICS VERSUS IN VIVO TESTING AND CLINICAL RESPONSE: There is evidence that when comparative testing is performed on inhaler devices using the same methods, there is some correlation between particle size measurements and clinical response. However, the measurements are dependent upon the methods used, and a single measure of a device in isolation is of limited value. Also, there is little data on comparing devices of different types. There is currently insufficient data to verify the ability of in vitro assessments to predict inhaler performance in vivo. RESULTS--EFFECTIVENESS OF METERED-DOSE INHALERS FOR THE DELIVERY OF CORTICOSTEROIDS IN ASTHMA: The review of three trials in children and 21 trials in adults demonstrated no evidence to suggest clinical benefits of any other inhaler device over a pMDI in corticosteroid delivery. RESULTS--EFFECTIVENESS OF METERED-DOSE INHALERS FOR THE DELIVERY OF BETA-AGONISTS IN STABLE ASTHMA: In children, 11 studies were reviewed, of which seven compared the Turbohaler with the pMDI. One study found a significant treatment difference in peak expiratory flow rate, although there were differences in the patients' baseline characteristics. In adults, a review of 70 studies found no demonstrable difference in the clinical bronchodilator effect of short-acting b2-agonists delivered by the standard pMDI compared with that produced by any other DPI, HFA-pMDI or the Autohaler device. The finding that HFA-pMDIs may reduce treatment failure and oral steroid requirement in beta-agonist delivery needs further confirmatory research in adequately randomised clinical trials. RESULTS--EFFECTIVENESS OF NEBULISERS VERSUS METERED-DOSE INHALERS FOR THE DELIVERY OF BRONCHODILATORS IN STABLE ASTHMA: In children, three included trials compared different devices with a nebuliser and demonstrated no evidence of clinical superiority of nebulisers over inhaler devices in bronchodilator delivery. A total of 23 studies in adults found no equivalence for the main pulmonary outcomes and no evidence of difference in other outcomes. RESULTS--EFFECTIVENESS OF METERED-DOSE INHALERS FOR THE DELIVERY OF BETA-AGONISTS IN COPD: Only two studies were included in this review. No evidence of clinical difference was found in beta-agonist delivery. RESULTS--EFFECTIVENESS OF NEBULISERS VERSUS METERED-DOSE INHALERS FOR THE DELIVERY OF BRONCHODILATORS IN COPD: Evidence from 14 trials demonstrated equivalence for the main outcomes of pulmonary function. For other outcomes there was no evidence of treatment difference in bronchodilator delivery. RESULTS--PATIENTS' ABILITY TO USE METERED-DOSE INHALERS: Differences among studies and the heterogeneity of the results make it difficult to draw conclusions about inhaler technique differences between device types. The review of technique after teaching the correct technique suggests that there is no difference in patients' ability to use DPI or pMDIs. RESULTS--ECONOMIC ANALYSIS: The total number of NHS prescriptions for inhaler therapy for asthma in 1998 was over 31 million, with a net ingredient cost in excess of 392 million GB pounds. This economic assessment uses decision analysis to estimate the relative cost-effectiveness of inhaler devices for the delivery of bronchodilator and corticosteroid inhaled therapy. Overall, there were no differences in patient outcomes among the devices. On the assumption that the devices were clinically equivalent, pMDIs were the most cost-effective devices for asthma treatment.

CONCLUSIONS

This systematic review examined the evidence from clinical trials evaluating the clinical effectiveness of different inhaler devices in the delivery of inhaled corticosteroids and beta2-bronchodilators for patients with asthma and COPD. The evidence from the published clinical literature demonstrates no difference in clinical effectiveness between nebulisers and alternative inhaler devices compared to standard pMDI with or without a spacer device. The cost-effectiveness evidence therefore favours pMDIs (or the cheapest inhaler device) as first-line treatment in all patients with stable asthma unless other specific reasons are identified. Patients can use pMDIs as effectively as other inhaler devices as long as the correct inhalation technique is taught. CONCLUSIONS--RECOMMENDATIONS FOR RESEARCH: Further clinical trials are required to demonstrate any differences in the clinical effectiveness and cost-effectiveness of inhaler devices and nebulisers compared with pMDIs. These should be of sufficient statistical power and methodological rigour to demonstrate any clinical benefit. Trials should be undertaken in community settings to ensure the generalisability of results. Outcome measures should be more patient-centred and report adverse effects more completely. Reporting of data from trials should be improved.

Drug treatments for obstructive sleep apnoea

BACKGROUND

The treatment of choice for moderate to severe obstructive sleep apnoea (OSA) is continuous positive airway pressure (CPAP) via a mask during sleep. However this is not tolerated by all patients and its role in mild OSA is not proven. Drug therapy has been proposed as an alternative to CPAP in some patients with mild to moderate sleep apnoea. The mechanisms by which drugs might reduce OSA include; a reduction in the proportion of rapid eye movement (REM) sleep (during which apnoeas tend to be more frequent), an increase in ventilatory drive or an increase in upper airway muscle tone during sleep.

OBJECTIVES

To determine the efficacy of drug therapies in the treatment of sleep apnoea.

SEARCH STRATEGY

Searches were carried out on the Cochrane Airways Group RCT Register. Additional hand searching was performed as relevant.

SELECTION CRITERIA

Double blind, randomised placebo controlled trials were included, involving patients with confirmed obstructive sleep apnoea. Trials were excluded if continuous positive airways pressure, mandibular devices or oxygen therapy were used. No restriction was placed upon publication language or trial duration.

DATA COLLECTION AND ANALYSIS

A total of 51 references were identified by electronic searches. 42 studies were retrieved for selection and 9 trials were included in the review. The results for 91 patients were available. No response for further information was forthcoming from the study authors. Results were expressed as (WMD) and 95% Confidence Intervals (95% CI) MAIN RESULTS: Only acetazolamide reduced the Hypopnoea Index (1 crossover trial of 9 patients, Weighted Mean Difference -24; 95%Confidence Intervals (95% CI): -4, -44). However there was no symptomatic response and the drug was poorly tolerated. Protriptyline led to a symptomatic improvement (improved vs not improved) in two out of three crossover trials (13 patients, Peto Odds Ratio 29.2; 95%CI 2.8, 301.1) but there was no change in the apnoea frequency. No beneficial effects were found for medroxy progesterone, clonidine, buspirone, aminophylline, theophylline or sabeluzole.

REVIEWER'S CONCLUSIONS

The data available do not support the use of drugs as a therapy for OSA. Although the studies examined had limitations there was little to justify further trials of these particular drugs.

Pressurised metered-dose inhalers versus all other hand-held inhalers devices to deliver bronchodilators for chronic obstructive pulmonary disease

BACKGROUND

Bronchodilator therapy for COPD may be delivered by a number of different inhaler devices.

OBJECTIVES

To determine the efficacy of pressurised metered dose inhalers (pMDI) compared to any other handheld inhaler device for the delivery of bronchodilators in non-acute COPD.

SEARCH STRATEGY

The Cochrane Collaboration, Asthma and Wheeze Randomised Controlled Clinical Trials register was searched for studies. The UK pharmaceutical companies who manufacture inhaled COPD medication were also contacted.

SELECTION CRITERIA

Two reviewers independently reviewed the results of computerised search and any potentially relevant articles were obtained in full.

DATA COLLECTION AND ANALYSIS

One reviewer extracted details of each trial and a second reviewer checked all extracted data. Dichotomous outcomes such as exacerbation rate were assessed using relative risk, with 95% confidence interval (CI).

MAIN RESULTS

Fourteen studies appeared potentially relevant but only three studies (61 patients) met the entry criteria. Two studies compared a dry powder device (Turbuhaler or Rotahaler) with a pMDI for beta2-agonist delivery, and one (36 patients cross-over design) the Respimat (soft mist device for ipratropium) vs a pMDI. For the Turbuhaler and Rotahaler, none of the reported outcome measures were significantly different. The Rotahaler study used a high and low dose of medication with or without large volume spacer. The study using the Respimat showed significant increases in FEV1 when compared to a pMDI (difference in change from base line 70 ml, 95% CI 10, 130 ml). The effect on change in FVC was of similar size. There were no differences between these two devices for any other reported outcomes. Although none of the included studies required prior patient ability to use any of the inhalers (and no study mentioned device training), it was assumed that all patients randomised into the study would have undergone training in use of the study inhalers and were capable of using those devices.

REVIEWER'S CONCLUSIONS

In patients with stable COPD, pMDI produced similar outcomes to a dry powder device for delivering beta2-agonists, but the very small number of studies and included patients does not permit firm conclusions to be drawn. The soft mist device for ipratropium was more effective than a pMDI, but the data come from one small study. There need to be further well designed randomised controlled trials to define the role of inhaler devices using bronchodilators in stable COPD.

Continuous positive airways pressure for obstructive sleep apnoea

BACKGROUND

Obstructive sleep apnoea is the periodic reduction (hypopnoea) or cessation (apnoea) of breathing due to narrowing or occlusion of the upper airway during sleep. The main symptom is daytime sleepiness although there it has been linked to premature death, hypertension, ischaemic heart disease, stroke and road traffic accidents.

OBJECTIVES

The main treatment for sleep apnoea is with continuous positive airways pressure (CPAP) treatment, which consists of a flow generator and mask. These are used at night to prevent apnoea, hypoxia and sleep disturbance. The objective was to assess the effects of CPAP in the treatment of obstructive sleep apnoea in adults.

SEARCH STRATEGY

We searched the Cochrane Airways Group RCT register (MEDLINE 1966 to 2000, Embase 1974 to 2000, Cinahl 1982 to 2000) and the reference lists of articles. We consulted experts in the field.

SELECTION CRITERIA

Randomised trials comparing nocturnal CPAP with placebo or other treatments in adults with obstructive sleep apnoea and an apnoea/hypopnoea index greater than five per hour.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed and two reviewers extracted data independently. Study authors were contacted for missing information.

MAIN RESULTS

Twelve trials involving 475 people were included. Most studies had methodological shortcomings. Most trials were of crossover design. Compared with placebo, CPAP showed significant improvements in objective and subjective sleepiness and several quality of life and depression measures. Patients preferred CPAP to placebo (odds ratio 0.4, 95% confidence interval 0.2 to 0.8). There was no significant effect on daytime blood pressure. Compared with oral appliances, CPAP significantly improved the apnoea/hypopnoea index (weighted mean difference -7.3, 95% confidence interval -10.0 to -4.7) and minimum oxygen saturation during sleep. Patients strongly preferred the oral appliance to CPAP (odds ratio 9.5, 95% confidence interval 4.3 to 21.1).

REVIEWER'S CONCLUSIONS

CPAP is more effective than placebo in improving sleepiness and quality of life measures for people with obstructive sleep apnoea. It is more effective than oral appliances in improving respiratory disturbances. Although patients prefer CPAP to placebo, they preference oral appliances to CPAP.

Exposure to increased pressure or hyperbaric oxygen suppresses interferon-gamma secretion in whole blood cultures of healthy humans

This study examines the effects of hyperoxia, increased atmospheric pressure, and hyperbaric oxygen on cytokine synthesis. Five healthy volunteers were exposed to 90 min of room air, 100% oxygen, 10.5% oxygen at 2 atm abs, or 100% oxygen at 2 atm abs (HBO2). All subjects were blinded and randomly exposed to each of the 4 conditions. Immediately before entering the chamber, immediately after exposure, and 3 and 24 h later, blood was drawn and stimulated ex vivo with phorbol myristate acetate (PMA) and phytohemagglutinin A (PHA). Since lymphocytes are the primary source of PMA/PHA-induced interferon-gamma (IFN-gamma), these results were expressed as IFN-gamma production per 10(6) lymphocytes. Following the HBO2 exposure, PMA/PHA-stimulated lymphocytes released 51% less IFN-gamma than cells obtained before the exposure. This suppression persisted for 24 h following HBO2 (P < 0.05). Surprisingly, increased atmospheric pressure alone also inhibited IFN-gamma secretion (P < 0.05). Room air and hyperoxia alone had no significant effect upon IFN-gamma release. HBO2's anti-inflammatory effect may, in part, be due to inhibition of IFN-gamma release.

The Otto E. Aufranc Award: The role of labral lesions to development of early degenerative hip disease

The current authors examined the hypothesis that labral lesions contribute to early degenerative hip disease. Between 1993 and 1999, 436 consecutive hip arthroscopies were done by the senior author. In addition, 54 acetabula were harvested from human adult cadavers. Two hundred forty-one of the 436 (55.3%) patients who had arthroscopies had a 261 labral tears, all located at the articular, not capsular margin of the labrum. Stereomicroscopic examination of the 54 acetabula from cadavers revealed 52 labral lesions. Overall, there was no significant difference between the arthroscopic and cadaveric populations in terms of the incidence of labral tears. (Overall, 73% of patients with fraying or a tear of the labrum had chondral change. Arthroscopic and anatomic observations support the concept that labral disruption and degenerative joint disease are frequently part of a continuum of joint disease.

Empowerment: a view of two low-income African-Americans communities

Field theory and empowerment were used as guiding conceptual frameworks to address empowerment issues in two low-income inner city African-Americans communities. Field theory and empowerment provided a conceptualization of these communities in terms of the possible impact of the physical environment of these communities on their residents and the health care professionals who worked with these residents. The most likely response is learned helplessness and depression that are antithetical to empowerment. These frameworks also were helpful in generating strategies to foster empowerment among these community residents. These strategies include helping residents to redefine their behavior as ways of coping with a hostile environment that confronts them with poverty and racism and to reconnect with natural supports in the community for the purpose of enhancing community coalitions and alliances.

The watershed labral lesion: its relationship to early arthritis of the hip

This study examined the hypothesis that labral lesions contribute to early degenerative hip disease. Between 1993 and 1999, 436 consecutive hip arthroscopies were performed by the senior author (J.C.M.). In addition, 54 acetabula were harvested from human adult cadavers and 10 hips underwent microangiography to determine labral blood supply. Of the 436 arthroscopic patients, 241 (55.3%) had a total of 261 labral tears, all located at the articular, not capsular, margin of the labrum. Stereomicroscopic examination of the 54 cadaver acetabula revealed a total of 52 labral lesions. Overall, there was no significant difference between the arthroscopic and cadaver populations in terms of the incidence of labral tears (P=.315). There was a high association between labral lesions and adjacent acetabular chondral damage. Arthroscopic and anatomic observations support the concept that labral disruption and degenerative joint disease frequently are part of a continuum of joint pathology.

Experimental infection of European red foxes (Vulpes vulpes) with canine herpesvirus

We report on the pathogenicity of canine herpesvirus (CHV) for European red foxes. In the first experiment, we inoculated 10 adult foxes intravenously with a canine isolate of CHV. All foxes became infected and shed CHV in saliva and genital secretions for up to 14 days post-inoculation (p.i.) as evaluated by PCR and/or by virus isolation. All foxes developed clinical signs such as fever, lethargy and evidence of respiratory tract disease. Two foxes died on day 6 p.i., one on day 7 p.i., and one fox was euthanased on day 6 p.i. Tissues taken from the four dead foxes were positive for CHV by PCR. The remaining six foxes recovered after approximately 14 days p.i. Virus particles with morphology typical of herpesviruses were found by electron microscopy in the liver of an infected animal. All surviving foxes developed serum anti-CHV antibodies. In a second experiment, six foxes were dosed perorally with CHV and paired with six untreated controls. Neither the perorally dosed nor the in-contact control foxes developed clinical signs of disease. Infectious CHV was not isolated from any of the dosed or the in-contact foxes but all perorally-infected foxes and one of the in-contact foxes tested PCR-positive for CHV on several occasions p.i. All perorally-infected foxes, but none of the in-contact foxes, seroconverted. In summary, intravenous CHV inoculation caused a clinical disease in adult foxes much more severe than observed in experimentally-infected adult dogs. No clinical disease or virus spread was observed after peroral dosing although viral infection occurred as evidenced by seroconversion.