Ammonia uptake and release in the MnX₂–NH₃ (X = Cl, Br) systems and structure of the Mn(NH₃)nX₂ (n = 6, 2) ammines

Hexa-ammine complexes, Mn(NH<sub>3</sub>)<sub>6</sub>X<sub>2</sub> (X = Cl, Br), have been synthesized by ammoniation of the corresponding transition metal halide and characterized by Powder X-ray diffraction (PXRD) and Raman spectroscopy. The hexa-ammine complexes are isostructural (Cubic,Fm-3m, Z = 4; a = 10.2742(6) Å and 10.527(1) Å for X = Cl, Br respectively). Temperature programmed desorption (TPD) demonstrated that ammonia release from Mn(NH<sub>3</sub>)<sub>6</sub>X<sub>2</sub> complexes occurred in three stages corresponding to the release of 4, 1 and 1 NH<sub>3</sub> equivalents respectively. The chloride and bromide both exhibit a deammoniation onset temperature below 323 K. The di-ammoniates from the first desorption step were isolated during TPD measurements and their crystal structures determined by Rietveld refinement against PXRD data (X = Cl: orthorhombicCmmm, a = 8.1991(9) Å, b = 8.2498(7) Å, c = 3.8212(4) Å, Z = 2; X = Br: orthorhombic Pbam, a = 6.0109(5) Å, b = 12.022(1) Å, c = 4.0230(2) Å, Z= 2)

Objective assessment of compliance and persistence among patients treated for glaucoma and ocular hypertension: a systematic review

Gregory Reardon1, Sameer Kotak2, Gail F Schwartz3 1Informagenics, LLC, Worthington, OH, USA; The Ohio State University College of Pharmacy, Columbus, OH, USA; 2Pfizer Inc, New York, NY, USA; 3Glaucoma Consultants, Greater Baltimore Medical Center; Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA Purpose: This study summarizes findings from objective assessments of compliance (or adherence) and persistence with ocular hypotensive agents in patients with glaucoma and ocular hypertension. Design: Systematic literature review. Methods: A PubMed and reference list search was conducted across publication years 1970–2010, using these terms and variants: "compliance," the equivalent term "adherence," and "persistence" in patients with these conditions and therapies. Summaries of selected studies were stratified by measurement method (electronic monitor, prescription fills review, medical chart review). Measures of central tendency across studies were calculated for commonly-reported compliance or persistence measures. Results: Fifty-eight articles met all inclusion/exclusion criteria: measurement of compliance–electronic monitoring (seven studies reported in 14 articles), measurement of compliance/persistence–prescription records (36 studies in 38 articles), and measurement of persistence–medical chart review (six studies in six articles). From electronic monitoring, most therapy-experienced patients took medication consistently, but ≥20% met criteria for poor compliance. From prescription records, only 56% (range 37%–92%) of the days in the first therapy year could be dosed with the medication supply dispensed over this period. At 12 months from therapy start, only 31% (range 10%–68%) of new therapy users had not discontinued, and 40% (range 14%–67%) had not discontinued or changed the initial therapy. From medical chart review, only 67% (range 62%–78%) of patients remained persistent 12 months after starting therapy. Conclusions: Evidence provided by this review suggests that poor compliance and persistence has been and remains a common problem for many glaucoma patients, and is especially problematic for patients new to therapy. The direction of empirical research should shift toward a greater emphasis on understanding of root causes and identification and testing of solutions for this problem. Keywords: persistence, adherence, glaucoma, ocular hypertension, revie

Incidence of Venous Thromboembolism in Nursing Home Residents

AbstractObjectiveVenous thromboembolism (VTE) is common in the elderly, but its epidemiology in nursing home residents remains unclear. This study estimated rates of VTE recorded on nursing home admission and incidence during residence.DesignRetrospective analysis of AnalytiCare long term care (LTC) database for the period January 2007 to June 2009.Setting181 nursing homes in 19 US states.ParticipantsEligible residents had 1 or more admission Minimum Data Set (MDS) 2.0 assessment(s) over the study period. All VTE cases were extracted if MDS indicated deep vein thrombosis or pulmonary embolism. The number of admissions and days at risk were estimated from a random sample (n = 1350) of all residents.MeasurementsThe earliest admission was identified as the admission index date. VTE cases were classified as either “On Admission” (VTE coded on admission index date) or “During Residence” (coded afterward). Residents were followed from admission index date until censoring.ResultsA total of 2144 VTE admission cases (3.7% of all admissions) were identified. A further 757 cases of VTE occurring during residence were identified, yielding an incidence of 3.68 cases of VTE per 100 person-years of postadmission residence. VTE admission rates were highest for residents younger than 50 years (4.8%, confidence interval [CI]: 3.9%–5.9%) and 50 to 64 years (5.1%, CI: 4.6%–5.7%) but similar for those aged 65 to 74 (3.6%, CI: 3.3%–4.0%), 75 to 84 (3.6%, CI: 3.3%–3.9%), and 85 years or older (3.1%, CI: 2.9%–3.4%). The incidence of VTE during residence was similar among these age strata.ConclusionApproximately 1 in 25 nursing home admissions had a VTE diagnosis. VTE incidence during residence was higher than reported in earlier nursing home studies. These incidence rates merit further investigation because diagnostic improvements may be driving greater recognition of VTE in LTC

I-LEEP Newsletter Volume 2, Issue 1

https://digitalcommons.lasalle.edu/ileep_newsletter/1004/thumbnail.jp

Facile synthesis of nanosized sodium magnesium hydride, NaMgH₃

The ternary magnesium hydride NaMgH3 has been synthesised via reactive milling techniques. The method employed neither a reactive H2 atmosphere nor high pressure sintering or other post-treatment processes. The formation of the ternary hydride was studied as a function of milling time and ball:powder ratio. High purity NaMgH3 powder (orthorhombic space group Pnma, a=5.437(2) Å, b=7.705(5) Å, c=5.477(2) Å; Z=4) was prepared in 5 h at high ball:powder ratios and characterised by powder X-ray diffraction (PXD), Raman spectroscopy and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX). The products formed sub-micron scale (typically 200–400 nm in size) crystallites that were approximately isotropic in shape. The dehydrogenation behaviour of the ternary hydride was investigated by temperature programmed desorption (TPD). The nanostructured hydride releases hydrogen in two steps with an onset temperature for the first step of 513 K

Improving pulsar-timing solutions through dynamic pulse fitting

Precision pulsar timing is integral to the detection of the nanohertz stochastic gravitational-wave background as well as understanding the physics of neutron stars. Conventional pulsar timing often uses fixed time and frequency-averaged templates to determine the pulse times of arrival, which can lead to reduced accuracy when the pulse profile evolves over time. We illustrate a dynamic timing method that fits each observing epoch using basis functions. By fitting each epoch separately, we allow for the evolution of the pulse shape epoch to epoch. We apply our method to PSR J1103$-$5403 and demonstrate that it undergoes mode changing, making it the fourth millisecond pulsar to exhibit such behaviour. Our method, which is able to identify and time a single mode, yields a timing solution with a root-mean-square error of 1.343 $\mu \mathrm{s}$, a factor of 1.78 improvement over template fitting on both modes. In addition, the white-noise amplitude is reduced 4.3 times, suggesting that fitting the full data set causes the mode changing to be incorrectly classified as white noise. This reduction in white noise boosts the signal-to-noise ratio of a gravitational-wave background signal for this particular pulsar by 32%. We discuss the possible applications for this method of timing to study pulsar magnetospheres and further improve the sensitivity of searches for nanohertz gravitational waves.Comment: Accepted in MNRAS, 8 pages, 8 figure

Achieving environmentally friendly building envelope for Western Australia’s housing sector: a Life Cycle Assessment approach

The rapid growth of Western Australia’s population and economy will affect the sustainability of its building sector. The energy consumption of all processes during mining to material production, transportation, construction plant and tools, and operation (heating, cooling, lighting, hot water and home appliances) stages causes high greenhouse gas (GHG) emissions and embodied energy (EE) consumption. The literature review to date have confirmed that the building envelope consisting of exterior walls, windows, external doors, roof, and floor could significantly affect the energy consumption during operation stage. Australian construction industry could thus enhance the energy efficiency of the building envelope in order to achieve its GHG emissions reduction targets. This paper has assessed the GHG emissions and EE consumption associated with the construction and use of a typical house in Perth for sixty building envelope options using a life cycle assessment (LCA) approach. The results show that the building envelope consisting of cast in situ sandwich wall with polyethylene terephthalate (PET) foam core, double glazed windows, and concrete roof tiles has the lowest life cycle GHG emissions and embodied energy consumption

Crystal Structure of the FeS Cluster–Containing Nucleotide Excision Repair Helicase XPD

DNA damage recognition by the nucleotide excision repair pathway requires an initial step identifying helical distortions in the DNA and a proofreading step verifying the presence of a lesion. This proofreading step is accomplished in eukaryotes by the TFIIH complex. The critical damage recognition component of TFIIH is the XPD protein, a DNA helicase that unwinds DNA and identifies the damage. Here, we describe the crystal structure of an archaeal XPD protein with high sequence identity to the human XPD protein that reveals how the structural helicase framework is combined with additional elements for strand separation and DNA scanning. Two RecA-like helicase domains are complemented by a 4Fe4S cluster domain, which has been implicated in damage recognition, and an α-helical domain. The first helicase domain together with the helical and 4Fe4S-cluster–containing domains form a central hole with a diameter sufficient in size to allow passage of a single stranded DNA. Based on our results, we suggest a model of how DNA is bound to the XPD protein, and can rationalize several of the mutations in the human XPD gene that lead to one of three severe diseases, xeroderma pigmentosum, Cockayne syndrome, and trichothiodystrophy