Effect of waste milk pasteurization on fecal shedding of Salmonella in preweaned calves

The objective of the current research was to determine if pasteurization of nonsaleable waste milk influences fecal Salmonella concentrations and prevalence, or antimicrobial susceptibility and serotype of the cultured isolates. Holstein dairy calves (n = 211) were housed on a single commercial dairy in the southwestern United States and randomly allotted to be fed either pasteurized (PWM; n = 128 calves) or nonpasteurized waste milk (NPWM; n = 83 calves). Fecal samples were collected via rectal palpation or from freshly voided, undisturbed fecal pats, weekly during the first 4 wk of the animal's life and then again at weaning. Eight total collections were made and 1,117 fecal samples cultured for Salmonella. One isolate from each culture-positive fecal sample was preserved for antimicrobial susceptibility screening and serotyping. Sixty-nine percent of the fecal samples were culture positive for Salmonella with no difference due to treatment (67.7 and 69% Salmonella positive for PWM and NPWM treatments, respectively). Few fecal samples (178/1,117; 15.9%) contained Salmonella concentrations above the limit of detection (～1 cfu/g of feces) with concentrations ranging from 1.0 to 6.46 cfu (log₁₀)/g of feces. Concentration was not affected by treatment. Seventeen different serotypes were identified, the majority of which were Montevideo and Anatum. A greater percentage of Typhimurium (87 vs. 13%), Muenchen (88 vs. 12%), and Derby (91 vs. 9%) were recovered from calves fed PWM compared with NPWM-fed calves. Conversely, Newport (12.5 vs. 86%), Bredeney (22.2 vs. 77.8%), and Muenster (12.5 vs. 87.5%) were lower in PWM compared with NPWM treatments. The majority (66.7%) of isolates were susceptible to all of the antibiotics examined. Results from this one commercial dairy suggest that milkborne Salmonella is not an important vector of transmission in dairy neonates, nor does pasteurization of waste milk influence fecal shedding of this pathogen. Caution should be used, however, when extrapolating results to other farms as Salmonella contamination of milk on farm is well documented. The potential benefits of pasteurization in disease prevention outweigh the potential risks of feeding a nonpasteurized product and warrants incorporation into any calf-rearing program using nonsaleable waste milk for feeding young dairy neonates.     

Renal transplantation in adults with thrombotic thrombocytopenic purpura/haemolytic-uraemic syndrome

BACKGROUND: Thrombotic thrombocytopenic purpura/haemolytic-uraemic syndrome (TTP/HUS) is a rare cause of renal failure in adults. There is little data concerning the outcome of adult patients who receive a renal transplant for TTP/HUS: METHODS: We have carried out a survey of 22 transplant centres in the USA to determine the outcome of patients who developed ESRD from TTP/HUS and latter received a renal transplant. RESULTS: Twelve of the 22 centres responded to our inquiry. Seven centres had not transplanted any patients with TTP/HUS, and five centres had transplanted a total of 24 grafts in 17 patients with TTP/HUS: Thirty-three per cent of patients demonstrated definite clinical and pathological evidence of recurrence of TTP/HUS: An additional 16% of patients demonstrated pathological evidence of possible recurrence of TTP/HUS in the absence of clinical manifestations. The overall 1-year graft survival rate was 42% and the 2-year graft survival rate was 35%. In our experience recurrence TTP/HUS was associated with universal graft failure. Although cyclosporin A does occasionally cause a thrombotic angiopathy in patients with no history of TTP/HUS, we found no evidence that it should be avoided in patients with a previous history of ESRD from TTP/HUS who subsequently receive a renal transplant. CONCLUSIONS: TTP/HUS frequently recurres in adults who receive a renal transplant, with a 2-year graft survival rate of 35%.     

Pertussis in Massachusetts, 1981-1991: incidence, serologic diagnosis, and vaccine effectiveness

Massachusetts provides diphtheria-tetanus toxoid-pertussis (DTP) vaccine, and since 1980 has monitored pertussis with a statewide diagnostic service. The incidence of bacteriologically confirmed pertussis was 104.5 per 100,000 person-years in 1-month-old infants and declined progressively thereafter. Infants < 6 months old experienced disproportionate morbidity: 44% of bacteriologically confirmed pertussis, 64% of hospitalizations, and 71% of hospital days. Most children with pertussis had received < 3 DTP doses during childhood, whereas 87% of adolescents with pertussis had received > or = 4 doses. Serodiagnosis by single serum anti-pertussis toxin antibody ELISA increased the incidence of confirmed pertussis in persons 11-19 years old from 3.0 to 12.9 per 100,000 and in persons > or = 20 years old from 0.16 to 0.56 per 100,000. Bacteriologic methods underestimate pertussis incidence, but a single serum anti-pertussis toxin antibody ELISA is a practical method for population-based diagnosis in adolescents and adults.     

Psychological and Physiological Adaptations to Sperm Competition in Humans.

Postcopulatory competition between males, in the form of sperm competition, is a widespread phenomenon in many animal species. The extent to which sperm competition has been an important selective pressure during human evolution remains controversial, however. The authors review critically the evidence that human males and females have psychological, behavioral, and physiological adaptations that evolved in response to selection pressures associated with sperm competition. The authors consider, using evidence from contemporary societies, whether sperm competition is likely to have been a significant adaptive problem for ancestral humans and examine the evidence suggesting that human males have physiological and psychological mechanisms that allow for "prudent" sperm allocation in response to variations in the risk of sperm competition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A system and methodologies for absolute quantum efficiency measurements from the vacuum ultraviolet through the near infrared

In this paper we present our system design and methodology for making absolute quantum efficiency (QE) measurements through the vacuum ultraviolet (VUV) and verify the system with delta-doped silicon CCDs. Delta-doped detectors provide an excellent platform to validate measurements through the VUV due to their enhanced UV response. The requirements for measuring QE through the VUV are more strenuous than measurements in the near UV and necessitate, among other things, the use of a vacuum monochromator, good dewar chamber vacuum to prevent on-chip condensation, and more stringent handling requirements.     

Increased cognitive load leads to impaired mobility decisions in seniors at risk for falls.

Successful mobility requires appropriate decision-making. Seniors with reduced executive functioning—such as senior fallers—may be prone to poor mobility judgments, especially under dual-task conditions. We classified participants as “At-Risk” and “Not-At-Risk” for falls using a validated physiological falls-risk assessment. Dual-task performance was assessed in a virtual reality environment where participants crossed a simulated street by walking on a manual treadmill while listening to music or conversing on a phone. Those “At-Risk” experienced more collisions with oncoming cars and had longer crossing times in the Phone condition compared to controls. We conclude that poor mobility judgments during a dual-task leads to unsafe mobility for those at-risk for falls. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Curing cycle modification for RTM6 to reduce hydrostatic residual tensile stress in 3D woven composites

Triaxial residual tensile stresses resulting after cooling a 3D woven composite from the curing temperature cause cracking in the resin pockets for weave architectures that have high through‐the‐thickness constraint. We show how curing cycle modifications can reduce the hydrostatic tensile stress generated by thermal mismatch during cooling of Hexcel RTM6 epoxy resin constrained in a quartz tube which simulates extreme constraint in a composite. The modified curing schedule consists of a high temperature cure to just before the glass transition, a lower temperature hold that takes the resin through the glass transition thereby freezing in the zero stress state, followed by high temperature cure to bring the resin to full conversion. We show that this process is sensitive to heating rates and can reduce the zero stress state of non‐toughened RTM6 resin to a temperature similar to a commercial rubber‐toughened resin, Cycom PR520. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43373.     

Growth of Listeria monocytogenes in different retail delicatessen meats during simulated home storage

Delicatessen meats are reported to be the leading vehicle of foodborne listeriosis in the United States. Listeria monocytogenes can reach high numbers in these products during storage, and the growth rate is largely dictated by product formulation and storage temperature. To assess the impact of product age on Listeria growth, five commercial brands each of cured and uncured turkey breast, ham, and roast beef (three lots per brand) were sliced (approximately 25 g per slice) at the beginning of the shelf life, the midpoint, and the last allowable day of sale, surface inoculated with an eight-strain cocktail of L. monocytogenes (approximately 40 CFU/g), and then quantitatively examined for Listeria, lactic acid bacteria, and mesophilic aerobic bacteria during aerobic storage at 4, 7, or 10°C. As expected, L. monocytogenes grew faster in deli meats without rather than with Listeria inhibitors (lactate and/or diacetate) and at the highest storage temperature (10°C). Lag-phase durations for L. monocytogenes in deli meats with and without Listeria inhibitors were 9.21, 6.96, and 5.00 and 6.35, 3.30, and 2.19 days at 4, 7, and 10°C, respectively. Generation times for L. monocytogenes in deli meats with and without Listeria inhibitors were 1.59, 1.53, and 0.85 and 0.94, 0.50, and 0.36 at 4, 7, and 10°C, respectively. Maximum population densities for L. monocytogenes in deli meats with and without Listeria inhibitors were 5.26, 5.92, and 5.97 and 8.47, 8.96 and 9.34 log CFU/g at 4, 7, and 10°C, respectively. Although lactate and diacetate suppressed L. monocytogenes growth, the extent of inhibition differed, ranging from total inhibition in roast beef to only partial inhibition in ham and cured turkey. Listeria growth was also impacted by lot-to-lot variation in the concentrations of Listeria inhibitors, product pH, and background microflora. These data will be useful for developing recommendations for "best consumed by" dating for deli meats using a risk-based approach.     

Preliminary investigation of flash sintering of SiC

The feasibility of flash sintering a covalent ceramic, SiC, has been investigated for the first time. Flash sintering involves the application of an electrical potential difference across a powder compact during heating, which leads to sintering at low furnace temperatures in a few seconds and has only been demonstrated with ionic ceramics previously. Near-theoretical density was achieved using Al₂O₃ + Y₂O₃ sintering aids at a furnace temperature of only 1170 °C and in a time of 150 s. Specimen temperatures were significantly higher than the furnace temperature owing to Joule heating and consequently heat loss limited densification in the near surface region. It was not possible to reach high densities using “ABC” sintering aids (aluminium–boron–carbon) or pure SiC. The mechanisms involved and potential commercial advantages are briefly discussed.     

An Ester of β-Hydroxybutyrate Regulates Cholesterol Biosynthesis in Rats and a Cholesterol Biomarker in Humans

In response to carbohydrate deprivation or prolonged fasting the ketone bodies, β‐hydroxybutyrate (βHB) and acetoacetate (AcAc), are produced from the incomplete β‐oxidation of fatty acids in the liver. Neither βHB nor AcAc are well utilized for synthesis of sterols or fatty acids in human or rat liver. To study the effects of ketones on cholesterol homeostasis a novel βHB ester (KE) ((R)‐3‐hydroxybutyl (R)‐3‐hydroxybutyrate) was synthesized and given orally to rats and humans as a partial dietary carbohydrate replacement. Rats maintained on a diet containing 30‐energy % as KE with a concomitant reduction in carbohydrate had lower plasma cholesterol and mevalonate (?40 and ?27 %, respectively) and in the liver had lower levels of the mevalonate precursors acetoacetyl‐CoA and HMG‐CoA (?33 and ?54 %) compared to controls. Whole liver and membrane LDL‐R as well as SREBP‐2 protein levels were higher (+24, +67, and +91 %, respectively). When formulated into a beverage for human consumption subjects consuming a KE drink (30‐energy %) had elevated plasma βHB which correlated with decreased mevalonate, a liver cholesterol synthesis biomarker. Partial replacement of dietary carbohydrate with KE induced ketosis and altered cholesterol homeostasis in rats. In healthy individuals an elevated plasma βHB correlated with lower plasma mevalonate.