A Study of heat-seal strength in the presence of edible oil surface contamination of ethylene-methacrylic acid copolymer films

Packages made from flexible film often use a heat-sealing process to ensure closure. The process involves joining two surfaces of film with heat and pressure across a period of time. Heat-seal problems arise when another substance partially obstructs the film-to-film contact. This substance acts as a surface contaminant. In packaging operations, the product being packaged is often the source of contamination in the sealing process. Testing heat-seal strength is a primary method for evaluating seal performance of flexible film. Test procedures require contaminant-free film samples to maintain accuracy and precision in results. This study altered the test method to explore the effects of contaminated samples. It was necessary to develop a contamination technique. The new technique applies an equal distribution of contamination for each sample. This study\u27s hypothesis is that a non-contaminated seal will be stronger than a contaminated seal. The findings supported that contamination could block film-to-film contact preventing a continuous seal, resulting in seal strengths less than a noncontaminated seal test. Results from two types of film and different seal temperatures supported the findings

Analyzing the Shape of Organizational Adaptability in Response to Environmental Jolts

Examining how organizational systems have responded to external jolts (threats, crises, etc.) is a useful precursor to large-scale organizational development projects. The shape of adaptability is introduced as a sensitizing concept for facilitating such analyses. The suggested elements of shape consist of three critical performance levels ([1] at the time of the jolt; [2] at the lowest point after any fall off in performance; and [3] its recovery level), and three time periods ([1] how long the organization is able to resist a fall off in performance [Resistance]; [2] how long it takes the organization to recover to its original performance level after a fall off [Resilience]; and [3] how long its recovery level lasts before decaying [Retention]). The success of the FAA\u27s passenger screening system in defending against hijackings is used as a vehicle for discussion

A perfect storm: An archaeological management crisis in the Mississippi River Delta

Engineered projects resulting in unintended consequences, coastal erosion, subsidence, and sea-level rise are rapidly destroying archaeological sites in the Mississippi River Delta (MRD). The processes of site obliteration are intensifying and accelerating due to anthropogenic transformation of the environment, including cumulative engineered alterations of the landscape and climate change. Combined with increased inundation and erosion from storm surges, hundreds of terrestrial sites formerly located on natural levees, barrier islands, and other coastal landforms are progressively eroded, redeposited, deeply buried, and submerged. These include thousand-year-old earthen mounds and shell middens constructed by Native Americans, as well as centuries-old fishing communities along the coast. These irreplaceable cultural properties can provide crucial information on the unique history and ecology of the MRD. Ongoing studies include consulting with interested parties and implementing data sharing agreements. Re- searchers have formed a consortium of universities and state and federal agencies, and are partnering with culturally affiliated Native American tribes, descendant groups, and coastal communities. The consortium is developing a robust GIS-enabled risk matrix for analyzing threats and effects to endangered sites. It is using the risk matrix to select 30 sites for monitoring, assessment, aerial photogrammetry, and recording environmental data on water table fluctuations. Analysis of action-based scientific data on these imperiled and rapidly disappearing places is urgently needed and will provide the impetus and baseline for future studies. Otherwise, ongoing site destruction will erase any remaining opportunities for learning about Louisiana’s deep history and diverse cultural heritage

S = 3 Ground State for a Tetranuclear Mn^(IV)₄O₄ Complex Mimicking the S₃ State of the Oxygen Evolving Complex

The S₃ state is currently the last observable intermediate prior to O–O bond formation at the oxygen-evolving complex (OEC) of Photosystem II, and its electronic structure has been assigned to a homovalent Mn^(IV)₄ core with an S = 3 ground state. While structural interpretations based on the EPR spectroscopic features of the S₃ state provide valuable mechanistic insight, corresponding synthetic and spectroscopic studies on tetranuclear complexes mirroring the Mn oxidation states of the S₃ state remain rare. Herein, we report the synthesis and characterization by XAS and multifrequency EPR spectroscopy of a Mn^(IV)₄O₄ cuboidal complex as a spectroscopic model of the S₃ state. Results show that this Mn^(IV)₄O₄ complex has an S = 3 ground state with isotropic ⁵⁵Mn hyperfine coupling constants of −75, −88, −91, and 66 MHz. These parameters are consistent with an αααβ spin topology approaching the trimer–monomer magnetic coupling model of pseudo-octahedral Mn^(IV) centers. Importantly, the spin ground state changes from S = 1/2 to S = 3 as the OEC is oxidized from the S₂ state to the S₃ state. This same spin state change is observed following oxidation of the previously reported Mn^(III)Mn^(IV)₃O₄ cuboidal complex to the Mn^(IV)₄O₄ complex described here. This sets a synthetic precedent for the observed low-spin to high-spin conversion in the OEC

Managing panic disorder in general practice

BACKGROUND: Panic disorder (PD) is common in the community and contributes to significant distress and decreased quality of life for people who suffer from it. Most people with PD will present in the first instance to their general practitioner or hospital emergency department for assistance, often with a focus on somatic symptoms and concerns. OBJECTIVE: This article aims to assist the GP to manage this group of patients by providing an outline of aetiology, approaches to assessment, and common management strategies. DISCUSSION Although GPs have an important role to play in ruling out any causal organic basis for panic symptoms, the diagnosis of PD can usually be made as a positive diagnosis on the basis of careful history taking. Thorough and empathic education is a vital step in management. The prognosis for PD can be improved by lifestyle changes, specific psychological techniques, and the judicious use of pharmacotherapy

EPR spectroscopy of iron- and nickel-doped [ZnAl]-layered double hydroxides: modeling active sites in heterogeneous water oxidation catalysts

Iron-doped nickel layered double hydroxides (LDHs) are among the most active heterogeneous water oxidation catalysts. Due to inter-spin interactions, however, the high density of magnetic centers results in line-broadening in magnetic resonance spectra. As a result, gaining atomic-level insight into the catalytic mechanism via electron paramagnetic resonance (EPR) is not generally possible. To circumvent spin-spin broadening, iron and nickel atoms were doped into non-magnetic [ZnAl]-LDH materials and the coordination environments of the isolated Fe(III) and Ni(II) sites were characterized. Multifrequency EPR spectroscopy identified two distinct Fe(III) sites (S = 5/2) in [Fe:ZnAl]-LDH. Changes in zero field splitting (ZFS) were induced by dehydration of the material, revealing that one of the Fe(III) sites is solvent-exposed (i.e. at an edge, corner, or defect site). These solvent-exposed sites feature an axial ZFS of 0.21 cm⁻¹ when hydrated. The ZFS increases dramatically upon dehydration (to -1.5 cm⁻¹), owing to lower symmetry and a decrease in the coordination number of iron. The ZFS of the other (“inert”) Fe(III) site maintains an axial ZFS of 0.19-0.20 cm⁻¹ under both hydrated and dehydrated conditions. We observed a similar effect in [Ni:ZnAl]-LDH materials; notably, Ni(II) (S = 1) atoms displayed a single, small ZFS (±0.30 cm⁻¹) in hydrated material, whereas two distinct Ni(II) ZFS values (±0.30 and ±1.1 cm⁻¹) were observed in the dehydrated samples. Although the magnetically-dilute materials were not active catalysts, the identification of model sites in which the coordination environments of iron and nickel were particularly labile (e.g. by simple vacuum drying) is an important step towards identifying sites in which the coordination number may drop spontaneously in water, a probable mechanism of water oxidation in functional materials

The players’ perspective of Reach Out Central : a therapeutic interactive online game

Therapeutic online games are potentially a valuable way of improving the mental health of young people. The purpose of this paper is to discuss the qualitative component of a formal evaluation conducted on Reach Out Central (ROC), an online game for 16-25 year olds which aims to improve mental health. Participants completing a post-program survey from the evaluation (n=154) were required to respond to two open-ended questions; what they liked most, and least, about ROC. Responses indicate that online games can be a successful way of educating, as well as attracting and engaging, young people. Suggestions are made regarding issues future developers should take into consideration when developing programs of a similar nature

Archaeological Testing of the Burleson Homestead at 41HY37 Hays County, Texas

At the request of Southwest Texas State University (now Texas State University-San Marcos), the Center for Archaeological Studies (CAS) conducted an archaeological excavation of the historic Burleson Homestead (41HY37). The excavation was conducted in June and July of 2000 under Texas Antiquities Committee Permit No. 2406. Artifacts collected during the project were processed and curated at CAS. In addition, CAS conducted archival research on structures located within the project boundaries. Upon completion of the excavation and archival research, a great deal has been learned concerning the Burleson ownership and use of the San Marcos Springs. Unfortunately, little intact evidence survives. CAS determined that the original cabin had been completely dismantled and a replica cabin was assembled nearby, but not on the original foundation . Most of the deposits on the ridge top have been disturbed and most of the recorded features relate to the construction of the replica cabin in the 1960s. The one early feature that does survive, Feature 4, should be preserved and used to provide a more accurate and full understanding of the locale when Edward Burleson settled the site and helped establish the community of San Marcos. CAS therefore recommends that no further archaeological investigations are necessary and that the site should be used to further the public education of the early history of the San Marcos Springs and the City of San Marcos