Neutron diffraction and gravimetric study of the manganese nitriding reaction under ammonia decomposition conditions

Manganese and its nitrides have recently been shown to co-catalyse the ammonia decomposition reaction. The nitriding reaction of manganese under ammonia decomposition conditions is studied in situ simultaneously by thermogravimetric analysis and neutron diffraction. Combining these complementary measurements has yielded information on the rate of manganese nitriding as well as the elucidation of a gamut of different manganese nitride phases. The neutron diffraction background was shown to be related to the extent of the ammonia decomposition and therefore the gas composition. From this and the sample mass, implications about the rate-limiting steps for nitriding by ammonia and nitriding by nitrogen are discussed

Sheep scab:comparison of spatial and temporal patterns determined by clinical diagnosis or ELISA

BACKGROUND: Ovine psoroptic mange (sheep scab) is an infectious condition caused by an allergen-induced hypersensitivity response to the mite Psoroptes ovis. Infestation results in clinical disease, economic loss and welfare issues in many sheep-producing countries. The aim of this study was to compare the prevalence and spatial pattern of sheep scab on contiguous farms, using both self-reported clinical outbreak history (2012–2020) and serological testing with an enzyme-linked immunosorbent assay (2021/2022). METHODS: Farms included in the study were located in three regions of known high scab prevalence in North, Central and Southwest England. In total, 254 farms completed both a questionnaire, which provided the clinical scab history of the farm, and submitted results of serological testing with the ELISA. RESULTS: A scab outbreak was reported by 17.4% (± confidence interval [CI]: 4.6%; n = 48) of farms in 2020 based on clinical diagnosis; scab was diagnosed by the ELISA on 25.6% (± 5.5%; n = 65) of farms in 2021/2022. Comparison of self-reported clinical scab cases with the ELISA test results identified a group of farms (n = 52) that did not report scab in 2020, or in some cases did not report having scab over the previous 8 years (n = 20), but whose flocks were nevertheless seropositive in 2021/2022. CONCLUSION: A small number of flocks, particularly those using common grazings in North England, where handling is infrequent, often comprising less susceptible sheep breeds, may have persistent scab infestations that are generally undetected by clinical inspection. The data highlight the advantages of serological testing to identify exposure to scab in flocks where clinical signs are less easily detected. GRAPHICAL ABSTRACT: [Image: see text

Revisiting the Benefits of Higher Education

The economic returns of higher education (HE) in terms of enhanced earnings are well established. The wider set of ‘non-economic benefits’ in the areas of health, generic skills and citizenship are less widely recognised. In an earlier report, we presented preliminary findings on the wider benefits, drawing on data collected at age 33 from the National Child Development Study (based on a cohort born in 1958). This report updates the earlier conclusions through new findings from a more extensive analysis involving both the 1958 cohort and the more recent 1970 British Cohort Study cohort (based on a cohort born in 1970). The current analysis incorporates more recent data collected in both cohorts in 2000 and at an older age (1958 cohort). We report findings in five major areas. First, we examine the mobility of graduates. To what extent do some parts of the country gain and lose graduates and graduate types of occupation at the expense of others? We then report findings on the ‘marginal returns’ to higher education in four domains of life: health, labour market, citizenship and values, and parenting

The Macrophage Scavenger Receptor A Is Host-Protective in Experimental Meningococcal Septicaemia

Macrophage Scavenger Receptor A (SR-A) is a major non-opsonic receptor for Neisseria meningitidis on mononuclear phagocytes in vitro, and the surface proteins NMB0278, NMB0667, and NMB1220 have been identified as ligands for SR-A. In this study we ascertain the in vivo role of SR-A in the recognition of N. meningitidis MC58 (serogroup B) in a murine model of meningococcal septicaemia. We infected wild-type and SR-A−/− animals intraperitoneally with N. meningitidis MC58 and monitored their health over a period of 50 hours. We also determined the levels of bacteraemia in the blood and spleen, and measured levels of the pro-inflammatory cytokine interleukin-6 (IL-6). The health of SR-A−/− animals deteriorated more rapidly, and they showed a 33% reduction in survival compared to wild-type animals. SR-A−/− animals consistently exhibited higher levels of bacteraemia and increased levels of IL-6, compared to wild-type animals. Subsequently, we constructed a bacterial mutant (MC58-278-1220) lacking two of the SR-A ligands, NMB0278 and NMB1220. Mutation of NMB0667 proved to be lethal. When mice were infected with the mutant bacteria MC58-278-1220, no significant differences could be observed in the health, survival, bacteraemia, and cytokine production between wild-type and SR-A−/− animals. Overall, mutant bacteria appeared to cause less severe symptoms of septicaemia, and a competitive index assay showed that higher levels of wild-type bacteria were recovered when animals were infected with a 1∶1 ratio of wild-type MC58 and mutant MC58-278-1220 bacteria. These data represent the first report of the protective role of SR-A, a macrophage-restricted, non-opsonic receptor, in meningococcal septicaemia in vivo, and the importance of the recognition of bacterial protein ligands, rather than lipopolysaccharide

Efficacy of Three-Week Oxytetracycline or Rifampin Monotherapy Compared with a Combination Regimen against the Filarial Nematode Onchocerca ochengi

Onchocerciasis (river blindness), caused by the filarial nematode Onchocerca volvulus, is a major cause of visual impairment and dermatitis in sub-Saharan Africa. As O. volvulus contains an obligatory bacterial symbiont (Wolbachia), it is susceptible to antibiotic chemotherapy, although current regimens are considered too prolonged for community-level control programs. The aim of this study was to compare the efficacies of oxytetracycline and rifampin, administered separately or in combination, against a close relative of O. volvulus (Onchocerca ochengi) in cattle. Six animals per group were treated with continuous or intermittent oxytetracycline regimens, and effects on adult worm viability, dermal microfilarial loads, and Wolbachia density in worm tissues were assessed. Subsequently, the efficacies of 3-week regimens of oxytetracycline and rifampin alone and a combination regimen were compared, and rifampin levels in plasma and skin were quantified. A 6-month regimen of oxytetracycline with monthly dosing was strongly adulticidal, while 3-week and 6-week regimens exhibited weaker adulticidal effects. However, all three regimens achieved >2-log reductions in microfilarial load. In contrast, rifampin monotherapy and oxytetracycline-rifampin duotherapy failed to induce substantive reductions in either adult worm burden or microfilarial load, although a borderline effect on Wolbachia density was observed following duotherapy. Dermal rifampin levels were maintained above the MIC for >24 h after a single intravenous dose. We conclude that oxytetracycline-rifampin duotherapy is less efficacious against O. ochengi than oxytetracycline alone. Further studies will be required to determine whether rifampin reduces oxytetracycline bioavailability in this system, as suggested by human studies using other tetracycline-rifampin combinations

Further evidence on auditor selection bias and the big 4 premium

In recent years, the competitiveness of the corporate audit market has received a great deal of attention from policy makers and academic researchers alike. Among the main issues of concern is whether large auditors command a premium when setting fees for statutory audit services, and whether this is symptomatic of a lack of competition in the market for audit services or results from differences in the quality of the product offered by the big 4. A large number of academic studies based on independent data sets find a positive OLS coefficient on a large auditor binary variable in audit fee regressions and interpret this as evidence of a premium. However, recent research on UK private companies suggests that the large auditor premium is explained by auditor self-selection bias and that when this is controlled for using a two-stage Heckman procedure, the premium vanishes. In this paper we examine some of the difficulties in properly specifying the audit fee equation and discuss potential sensitivity of the estimates provided by the two-step model. We re-estimate audit fee equations for over 36,000 UK private companies employing a relatively new development in the applied econometrics literature – propensity score matching. In addition, we employ formal decomposition methods, which have not been used in the audit literature to date, to provide a more comprehensive analysis of big 4 premiums. Our results suggest that evidence of the large auditor premium vanishing when selection bias is controlled for do not seem to generalise and that the Heckman two-step procedure is highly sensitive to model specification. Matching results suggest that auditees of similar size, risk and complexity pay significantly higher fees to big 4 auditors

UMF-078: A modified flubendazole with potent macrofilaricidal activity against Onchocerca ochengi in African cattle

<p>Abstract</p> <p>Background</p> <p>Human onchocerciasis or river blindness, caused by the filarial nematode <it>Onchocerca volvulus</it>, is currently controlled using the microfilaricidal drug, ivermectin. However, ivermectin does not kill adult <it>O. volvulus</it>, and in areas with less than 65% ivermectin coverage of the population, there is no effect on transmission. Therefore, there is still a need for a macrofilaricidal drug. Using the bovine filarial nematode <it>O. ochengi </it>(found naturally in African cattle), the macrofilaricidal efficacy of the modified flubendazole, UMF-078, was investigated.</p> <p>Methods</p> <p>Groups of 3 cows were treated with one of the following regimens: (a) a single dose of UMF-078 at 150 mg/kg intramuscularly (im), (b) 50 mg/kg im, (c) 150 mg/kg intraabomasally (ia), (d) 50 mg/kg ia, or (e) not treated (controls).</p> <p>Results</p> <p>After treatment at 150 mg/kg im, nodule diameter, worm motility and worm viability (as measured by metabolic reduction of tetrazolium to formazan) declined significantly compared with pre-treatment values and concurrent controls. There was abrogation of embryogenesis and death of all adult worms by 24 weeks post-treatment (pt). Animals treated at 50 mg/kg im showed a decline in nodule diameter together with abrogated reproduction, reduced motility, and lower metabolic activity in isolated worms, culminating in approximately 50% worm mortality by 52 weeks pt. Worms removed from animals treated ia were not killed, but exhibited a temporary embryotoxic effect which had waned by 12 weeks pt in the 50 mg/kg ia group and by 24 weeks pt in the 150 mg/kg ia group. These differences could be explained by the different absorption rates and elimination half-lives for each dose and route of administration.</p> <p>Conclusion</p> <p>Although we did not observe any signs of mammalian toxicity in this trial with a single dose, other studies have raised concerns regarding neuro- and genotoxicity. Consequently, further evaluation of this compound has been suspended. Nonetheless, these results validate the molecular target of the benzimidazoles as a promising lead for rational design of macrofilaricidal drugs.</p

Ammonia decomposition catalysis using lithium–calcium imide

Lithium–calcium imide is explored as a catalyst for the decomposition of ammonia. It shows the highest ammonia decomposition activity yet reported for a pure light metal amide or imide, comparable to lithium imide–amide at high temperature, with superior conversion observed at lower temperatures. Importantly, the post-reaction mass recovery of lithium–calcium imide is almost complete, indicating that it may be easier to contain than the other amide–imide catalysts reported to date. The basis of this improved recovery is that the catalyst is, at least partially, solid across the temperature range studied under ammonia flow. However, lithium–calcium imide itself is only stable at low and high temperatures under ammonia, with in situ powder diffraction showing the decomposition of the catalyst to lithium amide–imide and calcium imide at intermediate temperatures of 200–460 °C.</p

Can Posting be a Catalyst for Dating Violence? Social Media Behaviors and Physical Interactions

Although Social Media can fuel jealousy between romantic partners, by providing a convenient and socially acceptable means of monitoring one another’s online behavior, little has been written about the possible role of Social Media in Dating Violence. We examine if and how Social Media behaviors fuel victimization during physical interactions. In addition, we consider if and how one’s partner in a physical relationship attempts to manipulate his or her Social Media behaviors. We car- ried out parallel questionnaires using the Dating Violence Questionnaire (DVQ), using both the un- altered version of the instrument as well as one in which questions were adapted to the Social Me- dia setting (e.g., “Has your partner beaten you as a consequence of something you said or did on social media?”). Participants (n = 144), were equally selected from both genders, in a counterbal- anced experimental design. We assigned half of the participants (n =72) to the Control group, who were administered the unaltered instrument, and half to the Social Media group. Similar rates of Dating Violence were reported by both groups. Respondents in the Social Media group reported experiencing physical, sexual and psychological violence, because of something said or done on Social Media. We also found that physical interactions between the romantic partners affects and alters the Social Media behaviors; Social Media spaces were often monitored by one’s partner, and altered in response to the partner’s demands. Overall, those involved in stable relationships were less likely to have experienced victimization, with men reporting more victimization as compared to women. To conclude, up to 76% of respondents experienced some form of Dating Violence and up to 83% of respondents experienced some form of manipulation related to their Social Media use, demonstrating the significance of this phenomenon in the lives of today’s youth

Caspase-8 and c-FLIPL associate in lipid rafts with NF-kappaB adaptors during T cell activation.

Humans and mice lacking functional caspase-8 in T cells manifest a profound immunodeficiency syndrome due to defective T cell antigen receptor (TCR)-induced NF-kappaB signaling and proliferation. It is unknown how caspase-8 is activated following T cell stimulation, and what is the caspase-8 substrate(s) that is necessary to initiate T cell cycling. We observe that following TCR ligation, a small portion of total cellular caspase-8 and c-FLIP(L) rapidly migrate to lipid rafts where they associate in an active caspase complex. Activation of caspase-8 in lipid rafts is followed by rapid cleavage of c-FLIP(L) at a known caspase-8 cleavage site. The active caspase.c-FLIP complex forms in the absence of Fas (CD95/APO1) and associates with the NF-kappaB signaling molecules RIP1, TRAF2, and TRAF6, as well as upstream NF-kappaB regulators PKC theta, CARMA1, Bcl-10, and MALT1, which connect to the TCR. The lack of caspase-8 results in the absence of MALT1 and Bcl-10 in the active caspase complex. Consistent with this observation, inhibition of caspase activity attenuates NF-kappaB activation. The current findings define a link among TCR, caspases, and the NF-kappaB pathway that occurs in a sequestered lipid raft environment in T cells