Redefining shelter: humanitarian sheltering.

Shelter is one of the most 'intractable problems' in humanitarian aid and yet there is little clarity on an overarching definition. Terminology for shelter and housing is often conflated, and the most prominent definition does not fully reflect recent progress in the Shelter and Settlements Sector. This paper explores the varying terminology utilised in definitions of shelter within humanitarian aid since 1990, reflecting on the concepts of 'shelter' and 'housing', alongside surrounding perceptions of 'house' versus 'home', and related measures of adequacy. The current, most prolific definition is also deconstructed, demonstrating ambiguity in some of terminology such as 'dignity' and 'privacy', and revealing that interpretation of this definition depends on the reader's knowledge. Lastly, a new definition of 'sheltering' is proposed, encompassing five key reflections: the concept of process over object; the inclusion of communities and individuals; the commonality of long-term sheltering; the wider effects of shelter; and the impacts on host communities and environment.

Program Infrastructure the Key to Success: A Pilot Crosswalk Installation to Promote Walkability, Pedestrian Safety, and Physical Activity in the U.S. Virgin Islands.

BACKGROUND & AIMS: While physical inactivity can contribute to chronic diseases, regular activity like walking can help prevent them. In 2010, one in three adults in the U.S. Virgin Islands (USVI) was physically inactive, higher than most U.S. states and territories. There are few walkable destinations and sidewalks along streets in the USVI. Since community- and street-scale design features can influence walking, we convened a 3-day walkability institute in the USVI to (1) learn about physical activity and best practices for design and (2) develop public health infrastructure that supports implementation. Island teams were formed to develop and implement a territory-wide action plan, focused on passing a Complete Streets policy, and demonstration projects on the islands of St. Croix, St. John, and St. Thomas to advance and pass this policy. An example of the demonstration projects and their significance is the completed one in St. Croix, which is the focus of this article. METHODS: Island teams applied critical components of functioning program infrastructure as described in the Component Model of Infrastructure (CMI) such as engaged data, multilevel leadership, responsive plans and planning, and networked partnerships. We evaluated whether a crosswalk installation in St. Croix could alter driver and pedestrian behavior and create a safer environment for pedestrians. Observers recorded pedestrian crossing time, driver speed, and other behaviors before and after crosswalk installation. RESULTS: Pedestrians took significantly fewer average seconds to cross the street in the postdemonstration period (9.83) compared with predemonstration (13.4) (p = .03). Average car speed declined between the predemonstration (24.3) and long-term demonstration periods (p < .01) and from the postdemonstration (24.7) to the long-term demonstration period (18.2) (p < .01). A greater percentage of pedestrians used the crosswalk to cross the street between the postdemonstration (12.5%) and long-term demonstration periods (53.7%) (p < .01). IMPLICATIONS: The demonstration project in St. Croix shows that improvements to built environment infrastructure can increase safety for pedestrians, thus improving walkability in the USVI. We discuss the importance of CMI elements observed in the success of the St. Croix demonstration and its effectiveness in promoting a Complete Streets policy and the lack of these elements on St. John hindering progress there. Public health practitioners can apply the CMI to future physical activity promotion projects in the USVI and other settings as having functioning program infrastructure helps overcome challenges including natural disasters and a global pandemic and can achieve progress toward sustained policy and systems change.

Community and Street-Scale Supports for Walking in the US Virgin Islands Before the 2017 Hurricanes.

OBJECTIVES: To determine the prevalence of community and street-scale design features that promote walking across the US Virgin Islands (USVI). METHODS: In May 2016, the USVI Department of Health, with technical assistance from the Centers for Disease Control and Prevention, conducted a territory-wide audit with a validated tool. We selected street segments (n = 1114) via a 2-stage sampling method, and estimates were weighted to be representative of publicly accessible street length. RESULTS: Overall, 10.7% of the street length contained a transit stop, 11.3% had sidewalks, 21.7% had at least 1 destination (e.g., stores, restaurants), 27.4% had a traffic calming feature (e.g., speed humps), and 53.2% had at least some street lighting. Several features were less prevalent on residential streets compared with commercial streets, including transit stops, sidewalks, destinations, and street lighting (P < .01). CONCLUSIONS: Across the USVI, community and street-scale features supportive of walking were uncommon. Improving community and street-scale design in the USVI, particularly in residential areas, could increase physical activity by enhancing walkability and therefore improve public health. These data can be used to inform community planning in the USVI.

The development of an automated microscope image tracking and analysis system.

Microscopy image analysis plays a crucial role in understanding cellular behavior and uncovering important insights in various biological and medical research domains. Tracking cells within the time-lapse microscopy images is a fundamental technique that enables the study of cell dynamics, interactions, and migration. While manual cell tracking is possible, it is time-consuming and prone to subjective biases that impact results. In order to solve this issue, we sought to create an automated software solution, named cell analyzer, which is able to track cells within microscopy images with minimal input required from the user. The program of cell analyzer was written in Python utilizing the open source computer vision (OpenCV) library and featured a graphical user interface that makes it easy for users to access. The functions of all codes were verified through closeness, area, centroid, contrast, variance, and cell tracking test. Cell analyzer primarily utilizes image preprocessing and edge detection techniques to isolate cell boundaries for detection and analysis. It uniquely recorded the area, displacement, speed, size, and direction of detected cell objects and visualized the data collected automatically for fast analysis. Our cell analyzer provides an easy-to-use tool through a graphical user interface for tracking cell motion and analyzing quantitative cell images.

Mechanism of loosening of the Souter-Strathclyde total elbow replacement evidence from revision surgery.

Nine Souter-Strathclyde humeral and ulnar components retrieved from revision surgery for aseptic loosening were examined macro- and microscopically. The wear patterns were compared and photographed. Humeral components demonstrated no evidence of wear. All ulnar components exhibited similar wear patterns. Six of the nine exhibited macroscopic evidence taking the form of deep linear grooves on either the medial or lateral articulating surfaces. Microscopic examinations revealed wear on all nine, exhibited as disruption of the polyethylene machining lines on the articular surfaces, but almost complete preservation on the central gliding ridge. We believe our observations are explained by 'rocking' of the humeral component on the ulnar as a result of the congruent surfaces of the Souter-Strathclyde prosthesis, which resist rotational and translational movements, characteristic of the normal elbow.

Real time monitoring of the polymerisation of PMMA bone cement using Raman spectroscopy.

In this investigation Raman spectroscopy was shown to be a method that could be used to monitor the polymerisation of PMMA bone cement. Presently there is no objective method that orthopaedic surgeons can use to quantify the curing process of cement during surgery. Raman spectroscopy is a non-invasive, non-destructive technique that could offer such an option. Two commercially available bone cements (Palacos R and SmartSet HV) and different storage conditions (4 and 22 degrees C) were used to validate the technique. Raman spectroscopy was found to be repeatable across all conditions with the completion of the polymerisation process particularly easy to establish. All tests were benchmarked against current temperature monitoring methods outlined in ISO and ASTM standards. There was found to be close agreement with the standard methods and the Raman spectroscopy used in this study.

Sampling Methodology and Reliability of a Representative Walkability Audit.

Background: Physical inactivity is a public health concern in the US Virgin Islands (USVI). A contributing factor may be a lack of pedestrian infrastructure and other environmental supports for walking. In this manuscript, we describe the methods used to conduct a walkability audit of environmental features related to physical activity in the USVI. Methods: In 2016, volunteer auditors conducted the audit using a modified version of the Microscale Audit of Pedestrian Streetscapes tool. A two-stage sampling method was developed using publicly available census data to select a sample of estates (n=46) and street segments (n=1,550; 99.2 km) across the USVI. A subset of segments was audited by two independent auditors, and inter-rater reliability was assessed using Cohen's kappa and percent agreement. Results: Audits were completed on 1,114 segments (94.6 km), and estimates were weighted to represent accessible public street length in the study area (1,155.9 km). Most items on the audit tool (62.7%) demonstrated good to excellent reliability. We found that it was feasible to conduct a reliable audit of environmental features related to physical activity across a large sample of streets in the USVI. Conclusions: These methods can be replicated in other settings to collect comprehensive data that can be used to guide strategies to improve the walkability of communities.

In vitro study of mean loads and modes of failure of all-ceramic crowns cemented with light-cured or dual-cured luting cement, after 1 and 30 d of storage.

This study compared the mean loads and modes of failure of teeth restored with all-ceramic crowns (ACCs) cemented with dual-cured (RelyX ARC; 3M ESPE) or light-cured (RelyX Veneer; 3M ESPE) luting cements. Clinically, there are advantages of light-cured cements over the recommended dual-cured cements, namely increased working time, improved handling, colour stability, and a homogenous mix. Forty, sound, extracted, human, premolar teeth underwent a standardized preparation for ACCs. IPS Empress (Ivoclar-Vivadent) crowns of standard dimensions were fabricated and 20 were cemented with each cement. The crowns were stored for 1 or 30 d in water and subjected to a compressive load to failure at 0.017 mm s(-1). There were no significant differences in loads at failure, between each cement group, at each storage period, and there were no significant differences in loads at failure, for each cement, at 1 and 30 d of storage. There were also no significant differences in modes of failure between each cement group. Before recommending light-cured cement as an alternative to dual-cured cement for the cementation of all-ceramic crowns, further research is required to establish the depth of ceramic at which light-cured lutes fail to polymerize completely.

Evaluation of an accelerated aging medium for acrylic bone cement based on analysis of nanoindentation measurements on laboratory-prepared and retrieved specimens.

The thrust of the study was a critical evaluation of the efficacy of a medium (30% v/v H(2)O(2), at 60 degrees C) that has been suggested in a literature report as being suitable for simulating the oxidative aging process, seen in vivo, in the acrylic bone cement mantles of total hip and knee joint replacements. For this purpose, quasi-static and dynamic nanoindentation measurements were used to obtain material properties--elastic modulus, E; hardness, H; and the variation of the storage and loss moduli with the frequency of the applied indenting force--of PalacosR acrylic bone cement specimens after various periods of immersion (7, 14, 21, and 28 days) in the aging solution, and of specimens prepared from cement mantles retrieved from cemented total hip joint replacements after various times in vivo (0.92-21 years). Also, best-fit relationships were obtained between E and time in the H(2)O(2) solution (t), H and t, E and in vivo time (T), and H and T. This body of results points to the possibility that the aging solution is effective, although the evidence is not conclusive.

Critical comparison of two methods for the determination of nanomechanical properties of a material: application to synthetic and natural biomaterials.

Two methods used for determining the elastic modulus (E) and hardness (H) of a material--the original version of the well-known Oliver-Pharr Method, OOPM, and a variant of it called the Modified Slopes Method, MSM--were critically compared. The nanoindentation test results, of indenter load-versus-indenter displacement, were recorded for six series of specimens, three of commercially-available acrylic bone cements (Palacos R and Cemex XL) and three of bones (human, bovine, and mouse). In the first series, the specimens were prepared from Palacos R cement mantles retrieved from cemented total hip joint replacements after 11 months, 11 years, and 21 years in vivo. In the second and third series, the specimens were fabricated from hand- and vacuum-mixed dough of Cemex XL cement, respectively. In the fourth, fifth, and sixth series, the specimens were prepared from fresh frozen cortical bone of human tibia, plexiform bone from fresh bovine tibia, and femora from inbred mice, respectively. It was found that, for a given material, the values of E or H computed using OOPM and MSM are not significantly different. However, the recommendation is that MSM is preferable because it is straightforward-only the nanoindentation measurements and values of constants that depend on the geometry of the indenter used are needed. In contrast, when the OOPM is used, there is a critical input (the indenter tip area function), whose computation is problematic. The article also includes a succinct discussion of factors that affect the values of material properties computed from nanoindentation measurements, such as the loading rate and the surface roughness of the test specimen.

Pelvic orientation for total hip arthroplasty in lateral decubitus: can it be accurately measured?

INTRODUCTION: During total hip arthroplasty (THA), accurately predicting acetabular cup orientation remains a key challenge, in great part because of uncertainty about pelvic orientation. This pilot study aimed to develop and validate a technique to measure pelvic orientation; establish its accuracy in the location of anatomical landmarks and subsequently; investigate if limb movement during a simulated surgical procedure alters pelvic orientation. METHODS: The developed technique measured 3-D orientation of an isolated Sawbone pelvis, it was then implemented to measure pelvic orientation in lateral decubitus with post-THA patients (n = 20) using a motion capture system. RESULTS: Orientation of the isolated Sawbone pelvis was accurately measured, demonstrated by high correlations with angular data from a coordinate measurement machine; R-squared values close to 1 for all pelvic axes. When applied to volunteer subjects, largest movements occurred about the longitudinal pelvic axis; internal and external pelvic rotation. Rotations about the anteroposterior axis, which directly affect inclination angles, showed >75% of participants had movement within ±5° of neutral, 0°. CONCLUSIONS: The technique accurately measured orientation of the isolated bony pelvis. This was not the case in a simulated theatre environment. Soft tissue landmarks were difficult to palpate repeatedly. These findings have direct clinical relevance, landmark registration in lateral decubitus is a potential source of error, contributing here to large ranges in measured movement. Surgeons must be aware that present techniques using bony landmarks to reference pelvic orientation for cup implantation, both computer-based and mechanical, may not be sufficiently accurate.

Discovery of filarial nematode DNA in Amblyomma americanum in Northern Virginia.

Ticks collected in 2011 were screened for the presence of filarial nematode genetic material, and positive samples were sequenced for analysis. Monanema-like filarial nematode DNA was recently discovered in Amblyomma americanum in northern Virginia, marking the first time genetic material from this parasite has been discovered in ticks in the state. Phylogenetic analysis revealed that this material was directly related to a previously discovered filarial nematode in A. americanum populations in Maryland as well as recently identified parasites in Ixodes scapularis from southern Connecticut. Further study is warranted to visually confirm the presence of these nematodes, characterize their distribution, and determine if these ticks are intermediate hosts.

The effect of patient gait on the material properties of UHMWPE in hip replacements.

The wear of ultra-high molecular weight polyethylene (UHMWPE) acetabular components in total hip replacements (THRs) has been shown to be highly dependent on the direction of shear. Greatly reduced wear rates have been reported for unidirectional, compared to multidirectional, articulation in vitro. This work for the first time enables investigation of a relationship between clinical wear conditions, as determined by patient gait path, and the mechanical and structural changes that occur within the UHMWPE acetabular component. Individual patients' wear paths were determined prior to revision operation from hip joint kinematics measured by clinical gait analysis. The material properties of the acetabular components removed during the revision operation were subsequently analysed. A technique using Fourier transform infra- red analysis (FTIR) was developed to quantify the orientation of the individual UHMWPE lamellae. This study shows that there is a direct relationship between a patient's clinical gait path and the molecular properties of their UHMWPE acetabular socket. Patient kinematics are an important factor affecting the wear and long-term biocompatibility of UHMWPE used as a bearing surface in THR.

Critical evaluation of pulse-echo ultrasonic test method for the determination of setting and mechanical properties of acrylic bone cement: influence of mixing technique.

Currently there is no reliable objective method to quantify the setting properties of acrylic bone cements within an operating theatre environment. Ultrasonic technology can be used to determine the acoustic properties of the polymerising bone cement, which are linked to material properties and provide indications of the physical and chemical changes occurring within the cement. The focus of this study was the critical evaluation of pulse-echo ultrasonic test method in determining the setting and mechanical properties of three different acrylic bone cement when prepared under atmospheric and vacuum mixing conditions. Results indicated that the ultrasonic pulse-echo technique provided a highly reproducible and accurate method of monitoring the polymerisation reaction and indicating the principal setting parameters when compared to ISO 5833 standard, irrespective of the acrylic bone cement or mixing method used. However, applying the same test method to predict the final mechanical properties of acrylic bone cement did not prove a wholly accurate approach. Inhomogeneities within the cement microstructure and specimen geometry were found to have a significant influence on mechanical property predictions. Consideration of all the results suggests that the non-invasive and non-destructive pulse-echo ultrasonic test method is an effective and reliable method for following the full polymerisation reaction of acrylic bone cement in real-time and then determining the setting properties within a surgical theatre environment. However the application of similar technology for predicting the final mechanical properties of acrylic bone cement on a consistent basis may prove difficult.

Patients' perception of leg length discrepancy post total hip arthroplasty.

Perception of a leg length discrepancy post total hip arthroplasty (THA) is one of the most common sources of patient dissatisfaction and can have a direct influence on the considered success of the operation.This research examined postoperative perception of imposed limb discrepancies in a group of THA patients compared to a group of participants with no previous hip surgery. Two subgroups of THA patients were involved: those who did not perceive a difference in limb length following THA and those that did.Discrepancies were imposed in 2.5 mm increments. For discrepancies ≥5 mm, a significant number of participants were aware of a difference (74%). There was no significant difference in perception of imposed discrepancies between THA patients and participants with no previous hip surgery. THA patients who perceived a difference in their limb lengths postoperatively had significantly worse pain and oxford scores when compared to THA patients who perceived their limb lengths to be equal. Knowing the boundaries between LLDs that go undetected and those that patients are aware of could guide surgeons when evaluating the balance between correct soft tissue tension and the resulting unequal leg length. From these findings, discrepancies >5 mm are likely to be perceived. Whether this perception would lead directly to a negative outcome score and patient dissatisfaction is more complex to project and likely to be patient specific. Intraoperative methods to aid the controlled positioning of implanted components could help maintain and restore leg length to within an acceptable amount that patients cannot perceive.

Derivatization of phospholipids.

Phospholipids are major components of biological membranes. Without chemical derivatization, it is difficult to identify and quantitate phospholipids in biological samples. Chemical derivatization can improve both the selectivity and sensitivity of the analytes. This paper gives a full review, through March, 2002, of derivatization methods used for phospholipids in HPLC, CE and GC as well as the spray reagent used for TLC in the early days.

Spotted fever group rickettsiae in multiple hard tick species from Fairfax County, Virginia.

Spotted fever group rickettsiosis (SFGR) is a potentially fatal disease that has displayed increasing incidence in the United States in recent years. The most well-known and severe type of this disease is Rocky Mountain spotted fever, but there are other mild forms that occur. Recently, human infection with Rickettsia parkeri has been reported and linked with the tick Amblyomma maculatum. In 2010, a population of R. parkeri-infected A. maculatum was discovered in Fairfax County, Virginia, leading to increased surveillance of tick species. In this study, we report the presence of R. parkeri in Rhipicephalus sanguineus, Haemaphysalis leporispalustris, and Dermacentor variabilis in Fairfax County. R. parkeri was discovered in two Rh. sanguineus, one H. leporispalustris, and 17 D. variabilis. These findings suggest that spillover infections of R. parkeri may be occurring in tick species not typically associated with this pathogen; however, vector competence studies need to be conducted to determine if these tick species can serve as potential vectors for human SFGR.