National survey of Salmonella prevalence in lymph nodes of sows and market hogs

Livestock are known to harbor Salmonella in their gastrointestinal (GI) tract and lymphatic tissues. Pathogens may be transferred from the GI tract to external carcass surfaces during normal harvest procedures but can be mitigated by antimicrobial carcass interventions. Lymph nodes (LNs) are typically encased in fat and are protected from antimicrobial carcass surface treatments, thus serving as a possible root cause of foodborne illnesses attributed to Salmonella in meat products. Members of the pork industry are committed to food safety and want to better understand Salmonella as a potential contaminant in pork products. To establish a baseline of Salmonella prevalence in porcine LNs across the United States, 21 commercial pork harvest facilities, representing northern (n = 12) or southern (n = 9) geographical regions, participated in this study. As processing volumes allowed, 25 carcasses were selected from each establishment. From each carcass, left and right superficial inguinal LNs (n =1,014 LNs) were removed and pooled to yield one sample per animal or n = 507 total LN samples. Salmonella prevalence rates differed (P < 0.05) between hog types in both regions. Specifically, 6.4% of market hog and 37.0% of sow samples were Salmonella positive in the northern region. This was reversed in the southern region as 13.0% of market hog and 4.8% of sow samples were Salmonella positive. There also was a difference (P < 0.05) in prevalence rates between northern and southern regions for sows, but not market hogs (P > 0.05). Type of chilling method (conventional, blast, or other) used at each market hog facility (n = 12) was documented. In the northern region, prevalence rates of Salmonella across chilling types were as follows: 20.0%, 2.7%, and 1.3% positive samples for conventional, other, and blast chill methods, respectively. In the southern region, 20.0% of samples were positive for conventional, 0.0% for blast, and 12.0% for other chilling methods. In both regions, samples from conventionally chilled carcasses returned more (P < 0.05) positive results than any other chill method. Overall, the higher rate of Salmonella prevalence in northern sows warrants further investigation, and members of the pork industry would benefit from the identification of possible methods to address the presence of Salmonella in porcine LNs.

Systematics of the frogs allocated to Sarcohyla bistincta sensu lato (Cope, 1877), with description of a new species from Western Mexico

A new species of hylid frog is described from the southwestern edge of the Mexican Plateau from the states of Morelos and Mexico through Michoacán and Jalisco, reaching the Sierra Madre Occidental in Sinaloa and western Durango. The new species is part of the widespread Mexican hylid Sarcohyla bistincta (sensu amplo) complex, comprised of S. bistincta, S. pentheter, S. calthula, and S. ephemera. One subspecies of S. bistincta (labeculata) was proposed for an isolated population in Oaxaca. We restrict the group's nominal species, S. bistincta (sensu stricto), to the Sierra Madre Oriental of Mexico and southward into the Sierra Madre del Sur of Guerrero and Oaxaca. Examination of type material places S. calthula and S. ephemera in the synonymy of S. labeculata (new combination). The species allied to S. bistincta, namely, S. bistincta, S. labeculata, S. pentheter, and the new species described herein, are diagnosed and described following recent suggested taxonomic changes and new available material.

Taxonomic review of the rare Mexican snake genus Chersodromus (Serpentes: Dipsadidae), with the description of two new species

Chersodromus is an endemic Mexican genus of snakes characterized by fused prefrontals shield. Only two species were previously known within the genus, C. liebmanni and C. rubriventris. We describe two new congeners, one from the Sierra Madre Oriental of northern Puebla and another from the Atlantic lowlands of the Chimalapas region in southeastern Oaxaca. These new species can be clearly differentiated on the basis of their morphology. Diagnostic characters distinguishing congeners include the number of dorsal scale rows, supralabials, and infralabials contacting anterior chinshields; whether or not the mental contacts the first pair of chinshields; and the coloration of the belly. We provide hemipenal descriptions of three species for which males are known.

Laying Waste to Mercury: Inexpensive Sorbents Made from Sulfur and Recycled Cooking Oils

Mercury pollution threatens the environment and human health across the globe. This neurotoxic substance is encountered in artisanal gold mining, coal combustion, oil and gas refining, waste incineration, chloralkali plant operation, metallurgy, and areas of agriculture in which mercury-rich fungicides are used. Thousands of tonnes of mercury are emitted annually through these activities. With the Minamata Convention on Mercury entering force this year, increasing regulation of mercury pollution is imminent. It is therefore critical to provide inexpensive and scalable mercury sorbents. The research herein addresses this need by introducing low-cost mercury sorbents made solely from sulfur and unsaturated cooking oils. A porous version of the polymer was prepared by simply synthesising the polymer in the presence of a sodium chloride porogen. The resulting material is a rubber that captures liquid mercury metal, mercury vapour, inorganic mercury bound to organic matter, and highly toxic alkylmercury compounds. Mercury removal from air, water and soil was demonstrated. Because sulfur is a by-product of petroleum refining and spent cooking oils from the food industry are suitable starting materials, these mercury-capturing polymers can be synthesised entirely from waste and supplied on multi-kilogram scales. This study is therefore an advance in waste valorisation and environmental chemistry.

Oxygen Scavengers affect Gas Mixture and Color Stability of Master Packed Ground Beef

This study investigated the effect of storage time, display time, oxygen scavengers, and carbon dioxide concentration on master packed ground beef color and package characteristics. Samples were stored at 0.5°C for up to 28 d in 20% CO2/80% N2 and 30% CO2/70% N2. Results indicated that red meat color was maintained for up to 28 d of storage. Nevertheless, a* values (meat redness) decreased during display as storage time increased (p < 0.05). Master packs with 2 types of oxygen scavengers showed comparable total carbon dioxide absorbed. However, differences between oxygen scavengers were noticed in packages that did not include meat. Carbon dioxide significantly decreased by 14 d of storage in packages with oxygen scavengers (p < 0.05), and remained low for the duration of the study. Carbon dioxide absorption by an oxygen scavenger is an important factor when considering the headspace gas and specific oxygen scavenger used in a modified atmosphere packaging system.

Studies on a Miscible Polyimide Blend

Blends of polyimides XU-218 and PEI were investigated using differential scanning calorimetry, dynamic mechanical analysis, thermogravimetric analysis and adhesive bond testing. The thermal stability of the blends increased as the proportion of PEI increased while the α-relaxation of the blends occurred at a slower rate and was broader and more cooperative in some blends, compared with the pure polymers. Physical aging of the pure polymers and blends in the glass state revealed changes in relaxation rate and lost enthalpy that were also consistent with blends not behaving as simple mixtures. The dynamic mechanical and physical aging behaviour was attributed to an increase in density on blending which decreased the unoccupied volume and increased the constraints on molecular mobility, as well as to the presence of concentration fluctuations. The adhesive properties of the blends were also investigated and bond strength was found to vary with blend composition and test temperature.

Fate of Pathogenic Bacteria Associated with Production of Pickled Sausage by Using a Cold Fill Process

Preservation by pickling has been used for many years to extend the shelf life of various types of food products. By storing meat products in a brine solution containing an organic acid, salt, spices, as well as other preservatives, the pH of the product is reduced, thus increasing the safety and shelf life of the product. Pickling may involve the use of heated brines to further add to the safety of the food product. When precooked, ready-to-eat (RTE) sausages are pickled with a heated brine solution, the process is referred to as hot filling. However, hot filling has been shown to affect the clarity of the brine, making the product cloudy and unappealing to consumers. Because of the potential quality defects caused by higher temperatures associated with hot fill pickling, cold fill pickling, which uses room temperature brine, is preferred by some pickled sausage manufacturers. Because little information exists on the safety of cold fill, pickled sausages, a challenge study was designed using a brine solution (5% acetic acid and 5% salt at 25°C) to pickle precooked, RTE sausages inoculated with a pathogen cocktail consisting of Salmonella Typhimurium, Salmonella Senftenberg, Salmonella Montevideo, Listeria monocytogenes , and Staphylococcus aureus . All pathogens were reduced ~6.80 log CFU/g in 72 h when enumerated on nonselective media. On selective media, Salmonella and L. monocytogenes decreased 6.33 and 6.35 log CFU/g in 12 h, respectively whereas S. aureus was reduced 6.80 log CFU/g in 24 h. Sausages experienced significant (P ≤ 0.05) decreases in pH over the 28 days of storage, whereas no significant differences were observed in water activity (P =0.1291) or salt concentration of the sausages (P =0.1445) or brine (P =0.3180). The results of this experiment demonstrate that cold fill pickling can effectively reduce and inhibit bacterial pathogens.

Diverse approaches to the health economic evaluation of bariatric surgery: a comprehensive systematic review

BACKGROUND

Health economic evaluations inform healthcare resource allocation decisions for treatment options for obesity including bariatric/metabolic surgery. As an important advance on existing systematic reviews, we aimed to capture, summarize and synthesize a diverse range of economic evaluations on bariatric surgery.

METHODS

Studies were identified by electronic screening of all major biomedical/economic databases. Studies included if they reported any quantified health economic cost and/or consequence with a measure of effect for any type of bariatric surgery from 1995 to September 2015. Study screening, data extraction and synthesis followed international guidelines for systematic reviews.

RESULTS

Six thousand one hundred eighty-seven studies were initially identified. After two levels of screening, 77 studies representing 17 countries (56% USA) were included. Despite study heterogeneity, common themes emerged, and important gaps were identified. Most studies adopted the healthcare system/third-party payer perspective; reported costs were generally healthcare resource use (inpatient/shorter-term outpatient). Out-of-pocket costs to individuals, family members (travel time, caregiving) and indirect costs due to lost productivity were largely ignored. Costs due to reoperations/complications were not included in one-third of studies. Body-contouring surgery included in only 14%. One study evaluated long-term waitlisted patients. Surgery was cost-effective/cost-saving for severely obese with type 2 diabetes mellitus. Study quality was inconsistent.

DISCUSSION

There is a need for studies that assume a broader societal perspective (including out-of-pocket costs, costs to family and productivity losses) and longer-term costs (capture reoperations/complications, waiting, body contouring), and consequences (health-related quality-of-life). Full economic evaluation underpinned by reporting standards should inform prioritization of patients (e.g. type 2 diabetes mellitus with body mass index 30 to 34.9 kg/m(2) or long-term waitlisted) for surgery. © 2016 World Obesity.

A new species of Rhadinella (Serpentes: Colubridae) from the Sierra Madre del Sur of Guerrero, Mexico

We describe a new species of Rhadinella from the Sierra Madre del Sur of Guerrero, Mexico, a region where the genus was previously unknown. This diminutive species is a member of a group of snakes previously allocated in the Rhadinaea godmani group, and more recently transferred to the genus Rhadinella. These snakes may have conspicuous dark longitudinal striping on a pale brown to orange background or may have dark brown to blackish dorsal ground coloration, which mostly or completely obfuscates a pattern of longitudinal striping. The new species is mostly dark with barely discernible slightly paler or darker striping (depending on how striping is interpreted). The closest relative of the new species, on the basis of morphological similarities and biogeography, appears to be Rhadinella donaji which occurs to the east in the Sierra Madre del Sur of Oaxaca about 275 km from the type-locality of the new species.

Sulfur-Limonene Polysulfide: A Material Synthesized Entirely from Industrial By-Products and Its Use in Removing Toxic Metals from Water and Soil

A polysulfide material was synthesized by the direct reaction of sulfur and d-limonene, by-products of the petroleum and citrus industries, respectively. The resulting material was processed into functional coatings or molded into solid devices for the removal of palladium and mercury salts from water and soil. The binding of mercury(II) to the sulfur-limonene polysulfide resulted in a color change. These properties motivate application in next-generation environmental remediation and mercury sensing.

A new species of Rhadinella (Serpentes: Colubridae) from the Pacific versant of Oaxaca, Mexico

I describe a new species of Rhadinella from the Pacific versant of Oaxaca, Mexico, a region where the genus was previously unknown. This diminutive snake is a member of a group of snakes that have dark dorsal coloration, which mostly or completely obfuscates a pattern of longitudinal striping characteristic of most species of Rhadinella. The closest relative of the new species, on the basis of morphological similarities, appears to be Rhadinella pilonaorum which occurs to the east of the Isthmus of Tehuantepec about 800 km from the type-locality of the new species.

Synthesis and Characterisation of High Fullerene Content Polymers and Their Use in Organic Photovoltaic Devices

Narrow dispersity polymers with a high tethered fullerene content were synthesised by first polymerising poly(chloromethyl styrene) using reversible addition–fragmentation chain transfer (RAFT) polymerisation and subsequently functionalising them with pristine fullerene. The polymers comprised 52 % by weight fullerene, corresponding to approximately one fullerene per monomer in the polymer with a different morphology to poly(3-hexyl thiophene) (P3HT) : phenyl-C61-butyric acid methyl ester (PCBM) systems. Bulk heterojunctions formed from the polymer tethered fullerene (PTF) with P3HT yielded functioning organic photovoltaic devices with power conversion efficiencies ranging from 0.0030 to 0.22 % as the PTF was increased from 1 : 0.8 to 1 : 1.3. Process optimisation resulted in a maximum efficiency of 0.4 %.