Saturation Spectroscopy of Iodine in Hollow-core Optical Fibre

We present high-resolution spectroscopy of Iodine vapour that is loaded and trapped within the core of a hollow-core photonic crystal fibre (HC-PCF). We compare the observed spectroscopic features to those seen in a conventional iodine cell and show that the saturation characteristics differ significantly. Despite the confined geometry it was still possible to obtain sub-Doppler features with a spectral width of ~6 MHz with very high contrast. We provide a simple theory which closely reproduces all the key observations of the experiment.Comment: 12 pages, 7 figure

Elective surgery system strengthening: development, measurement, and validation of the surgical preparedness index across 1632 hospitals in 119 countries

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index to support local elective surgical system strengthening and address growing backlogs. Methods First, we performed an international consultation through a four-stage consensus process to develop a multidomain index for hospital-level assessment (surgical preparedness index; SPI). Second, we measured surgical preparedness across a global network of hospitals in high-income countries (HICs), middle-income countries (MICs), and low-income countries (LICs) to explore the distribution of the SPI at national, subnational, and hospital levels. Finally, using COVID-19 as an example of an external system shock, we compared hospitals' SPI to their planned surgical volume ratio (SVR; ie, operations for which the decision for surgery was made before hospital admission), calculated as the ratio of the observed surgical volume over a 1-month assessment period between June 6 and Aug 5, 2021, against the expected surgical volume based on hospital administrative data from the same period in 2019 (ie, a pre-pandemic baseline). A linear mixed-effects regression model was used to determine the effect of increasing SPI score. Findings In the first phase, from a longlist of 103 candidate indicators, 23 were prioritised as core indicators of elective surgical system preparedness by 69 clinicians (23 [33%] women; 46 [67%] men; 41 from HICs, 22 from MICs, and six from LICs) from 32 countries. The multidomain SPI included 11 indicators on facilities and consumables, two on staffing, two on prioritisation, and eight on systems. Hospitals were scored from 23 (least prepared) to 115 points (most prepared). In the second phase, surgical preparedness was measured in 1632 hospitals by 4714 clinicians from 119 countries. 745 (45·6%) of 1632 hospitals were in MICs or LICs. The mean SPI score was 84·5 (95% CI 84·1–84·9), which varied between HIC (88·5 [89·0–88·0]), MIC (81·8 [82·5–81·1]), and LIC (66·8 [64·9–68·7]) settings. In the third phase, 1217 (74·6%) hospitals did not maintain their expected SVR during the COVID-19 pandemic, of which 625 (51·4%) were from HIC, 538 (44·2%) from MIC, and 54 (4·4%) from LIC settings. In the mixed-effects model, a 10-point increase in SPI corresponded to a 3·6% (95% CI 3·0–4·1; p<0·0001) increase in SVR. This was consistent in HIC (4·8% [4·1–5·5]; p<0·0001), MIC (2·8 [2·0–3·7]; p<0·0001), and LIC (3·8 [1·3–6·7%]; p<0·0001) settings. Interpretation The SPI contains 23 indicators that are globally applicable, relevant across different system stressors, vary at a subnational level, and are collectable by front-line teams. In the case study of COVID-19, a higher SPI was associated with an increased planned surgical volume ratio independent of country income status, COVID-19 burden, and hospital type. Hospitals should perform annual self-assessment of their surgical preparedness to identify areas that can be improved, create resilience in local surgical systems, and upscale capacity to address elective surgery backlogs

Report on an all-sky LIGO search for periodic gravitational waves in the S4 data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1000 Hz and having a negative frequency time derivative with magnitude between zero and $10^{-8}$ Hz/s. Data from the fourth LIGO science run have been used in this search. Three different semi-coherent methods of summing strain power were applied. Observing no evidence for periodic gravitational radiation, we report upper limits on strain amplitude and interpret these limits to constrain radiation from rotating neutron stars.Comment: 5 pages, 1 figure, presented at Amaldi7, Sydney (July 2007

Searching for stochastic gravitational-wave background with the co-located LIGO interferometers

This paper presents techniques developed by the LIGO Scientific Collaboration to search for the stochastic gravitational-wave background using the co-located pair of LIGO interferometers at Hanford, WA. We use correlations between interferometers and environment monitoring instruments, as well as time-shifts between two interferometers (described here for the first time) to identify correlated noise from non-gravitational sources. We veto particularly noisy frequency bands and assess the level of residual non-gravitational coupling that exists in the surviving data.Comment: Proceedings paper from the 7th Edoardo Amaldi Conference on Gravitational Waves, held in Sydney, Australia from 8-14 July 2007. Accepted to J. Phys.: Conf. Se

Phase II Investigations at Prehistoric and Rock Art Sites, Justiceburg Reservoir, Garza and Kent Counties, Texas Volume I

Phase II cultural resources investigations at the proposed Justiceburg Reservoir in Garza and Kent counties, Texas, were conducted by Prewitt and Associates, Inc. in 19881989. This report documents the archeological work at 62 prehistoric and aboriginal rock art sites and the geoarcheological study conducted as part of the Phase II work. Investigations at 48 prehistoric sites, including open campsites, rockshelters, lithic procurement sites, faunal localities, and rock art sites, resulted in complete National Register assessments; 9 campsites, the 2 rockshelters, and 6 rock art sites are considered to be eligible for listing on the National Register of Historic Places. Less-intensive investigations at 14 prehistoric sites yielded insufficient data for full National Register assessments. The geoarcheological study resulted in the formulation of a model of the geomorphic history of the project area. Of considerable importance is the recognition of a period of catastrophic flushing of alluvial sediments Within the Double Mountain ~ork valley during the middle Holocene, followed by late Holocene sedimentation and stabilization. This supports the concept of a dry middle Holocene Altitherrnal period and helps explain the biased archeological record in the project area. The prehistoric site investigations indicate that most of the archeological remains present at Justiceburg Reservoir date to the late Archaic and Late Prehistoric periods, a phenomenon noted in similar settings elsewhere in the Lower Plains. Of the open campsites assessed as eligible for listing on the National Register, four are classified as late Archaic (4500-2000 B.P.), two are classified as Late Prehistoric I (2000-1000 8.P.), and three are classified as Late Prehistoric II (1000 B.P. to evidence of European contact). The two investigated rockshelters contain evidence of Late Prehistoric I and II occupations. Due to the paucity of regional archeological data and the lack of a well-defined cultural chronology, only two of these sites can be assigned tentatively to recognized cultural complexes. Site 4lGR291 yielded ceramics and arrow points indicating a Palo Duro Complex occupation, ca. A.D. 500, while ceramics and a distinctive hearth associated with the upper component at 41KTS3 suggest a Garza Complex occupation, ca. A.D. 1600-1700. No evidence of European contact was found at any of the habitation sites, but three of the rock art sites contain historic Plains Indian iconography. The investigations at the prehistoric sites resulted in the formulation of a late Holocene cuItural sequence for the project area. Analyses of the various classes of archeological evidence (e.g., artifacts, features, faunal remains) revealed broad cultural patterns that appear to reflect significant changes in subsistence strategies through time. It is suggested that these changes are related to late Holocene environmental conditions and corresponding shifts in the resource base. It is further suggested that bison were the most important resource controlling late Holocene human adaptations in the Texas Lower Plains

Phase II Investigations at Prehistoric and Rock Art Sites, Justiceburg Reservoir, Garza and Kent Counties, Texas Volume I

Phase II cultural resources investigations at the proposed Justiceburg Reservoir in Garza and Kent counties, Texas, were conducted by Prewitt and Associates, Inc. in 19881989. This report documents the archeological work at 62 prehistoric and aboriginal rock art sites and the geoarcheological study conducted as part of the Phase II work. Investigations at 48 prehistoric sites, including open campsites, rockshelters, lithic procurement sites, faunal localities, and rock art sites, resulted in complete National Register assessments; 9 campsites, the 2 rockshelters, and 6 rock art sites are considered to be eligible for listing on the National Register of Historic Places. Less-intensive investigations at 14 prehistoric sites yielded insufficient data for full National Register assessments. The geoarcheological study resulted in the formulation of a model of the geomorphic history of the project area. Of considerable importance is the recognition of a period of catastrophic flushing of alluvial sediments Within the Double Mountain ~ork valley during the middle Holocene, followed by late Holocene sedimentation and stabilization. This supports the concept of a dry middle Holocene Altitherrnal period and helps explain the biased archeological record in the project area. The prehistoric site investigations indicate that most of the archeological remains present at Justiceburg Reservoir date to the late Archaic and Late Prehistoric periods, a phenomenon noted in similar settings elsewhere in the Lower Plains. Of the open campsites assessed as eligible for listing on the National Register, four are classified as late Archaic (4500-2000 B.P.), two are classified as Late Prehistoric I (2000-1000 8.P.), and three are classified as Late Prehistoric II (1000 B.P. to evidence of European contact). The two investigated rockshelters contain evidence of Late Prehistoric I and II occupations. Due to the paucity of regional archeological data and the lack of a well-defined cultural chronology, only two of these sites can be assigned tentatively to recognized cultural complexes. Site 4lGR291 yielded ceramics and arrow points indicating a Palo Duro Complex occupation, ca. A.D. 500, while ceramics and a distinctive hearth associated with the upper component at 41KTS3 suggest a Garza Complex occupation, ca. A.D. 1600-1700. No evidence of European contact was found at any of the habitation sites, but three of the rock art sites contain historic Plains Indian iconography. The investigations at the prehistoric sites resulted in the formulation of a late Holocene cuItural sequence for the project area. Analyses of the various classes of archeological evidence (e.g., artifacts, features, faunal remains) revealed broad cultural patterns that appear to reflect significant changes in subsistence strategies through time. It is suggested that these changes are related to late Holocene environmental conditions and corresponding shifts in the resource base. It is further suggested that bison were the most important resource controlling late Holocene human adaptations in the Texas Lower Plains

Phase II Investigations at Prehistoric and Rock Art Sites, Justiceburg Reservoir, Garza and Kent Counties, Texas Volume I

Phase II cultural resources investigations at the proposed Justiceburg Reservoir in Garza and Kent counties, Texas, were conducted by Prewitt and Associates, Inc. in 19881989. This report documents the archeological work at 62 prehistoric and aboriginal rock art sites and the geoarcheological study conducted as part of the Phase II work. Investigations at 48 prehistoric sites, including open campsites, rockshelters, lithic procurement sites, faunal localities, and rock art sites, resulted in complete National Register assessments; 9 campsites, the 2 rockshelters, and 6 rock art sites are considered to be eligible for listing on the National Register of Historic Places. Less-intensive investigations at 14 prehistoric sites yielded insufficient data for full National Register assessments. The geoarcheological study resulted in the formulation of a model of the geomorphic history of the project area. Of considerable importance is the recognition of a period of catastrophic flushing of alluvial sediments Within the Double Mountain ~ork valley during the middle Holocene, followed by late Holocene sedimentation and stabilization. This supports the concept of a dry middle Holocene Altitherrnal period and helps explain the biased archeological record in the project area. The prehistoric site investigations indicate that most of the archeological remains present at Justiceburg Reservoir date to the late Archaic and Late Prehistoric periods, a phenomenon noted in similar settings elsewhere in the Lower Plains. Of the open campsites assessed as eligible for listing on the National Register, four are classified as late Archaic (4500-2000 B.P.), two are classified as Late Prehistoric I (2000-1000 8.P.), and three are classified as Late Prehistoric II (1000 B.P. to evidence of European contact). The two investigated rockshelters contain evidence of Late Prehistoric I and II occupations. Due to the paucity of regional archeological data and the lack of a well-defined cultural chronology, only two of these sites can be assigned tentatively to recognized cultural complexes. Site 4lGR291 yielded ceramics and arrow points indicating a Palo Duro Complex occupation, ca. A.D. 500, while ceramics and a distinctive hearth associated with the upper component at 41KTS3 suggest a Garza Complex occupation, ca. A.D. 1600-1700. No evidence of European contact was found at any of the habitation sites, but three of the rock art sites contain historic Plains Indian iconography. The investigations at the prehistoric sites resulted in the formulation of a late Holocene cuItural sequence for the project area. Analyses of the various classes of archeological evidence (e.g., artifacts, features, faunal remains) revealed broad cultural patterns that appear to reflect significant changes in subsistence strategies through time. It is suggested that these changes are related to late Holocene environmental conditions and corresponding shifts in the resource base. It is further suggested that bison were the most important resource controlling late Holocene human adaptations in the Texas Lower Plains

Phase II Investigations at Prehistoric and Rock Art Sites, Justiceburg Reservoir, Garza and Kent Counties, Texas Volume I

Phase II cultural resources investigations at the proposed Justiceburg Reservoir in Garza and Kent counties, Texas, were conducted by Prewitt and Associates, Inc. in 19881989. This report documents the archeological work at 62 prehistoric and aboriginal rock art sites and the geoarcheological study conducted as part of the Phase II work. Investigations at 48 prehistoric sites, including open campsites, rockshelters, lithic procurement sites, faunal localities, and rock art sites, resulted in complete National Register assessments; 9 campsites, the 2 rockshelters, and 6 rock art sites are considered to be eligible for listing on the National Register of Historic Places. Less-intensive investigations at 14 prehistoric sites yielded insufficient data for full National Register assessments. The geoarcheological study resulted in the formulation of a model of the geomorphic history of the project area. Of considerable importance is the recognition of a period of catastrophic flushing of alluvial sediments Within the Double Mountain ~ork valley during the middle Holocene, followed by late Holocene sedimentation and stabilization. This supports the concept of a dry middle Holocene Altitherrnal period and helps explain the biased archeological record in the project area. The prehistoric site investigations indicate that most of the archeological remains present at Justiceburg Reservoir date to the late Archaic and Late Prehistoric periods, a phenomenon noted in similar settings elsewhere in the Lower Plains. Of the open campsites assessed as eligible for listing on the National Register, four are classified as late Archaic (4500-2000 B.P.), two are classified as Late Prehistoric I (2000-1000 8.P.), and three are classified as Late Prehistoric II (1000 B.P. to evidence of European contact). The two investigated rockshelters contain evidence of Late Prehistoric I and II occupations. Due to the paucity of regional archeological data and the lack of a well-defined cultural chronology, only two of these sites can be assigned tentatively to recognized cultural complexes. Site 4lGR291 yielded ceramics and arrow points indicating a Palo Duro Complex occupation, ca. A.D. 500, while ceramics and a distinctive hearth associated with the upper component at 41KTS3 suggest a Garza Complex occupation, ca. A.D. 1600-1700. No evidence of European contact was found at any of the habitation sites, but three of the rock art sites contain historic Plains Indian iconography. The investigations at the prehistoric sites resulted in the formulation of a late Holocene cuItural sequence for the project area. Analyses of the various classes of archeological evidence (e.g., artifacts, features, faunal remains) revealed broad cultural patterns that appear to reflect significant changes in subsistence strategies through time. It is suggested that these changes are related to late Holocene environmental conditions and corresponding shifts in the resource base. It is further suggested that bison were the most important resource controlling late Holocene human adaptations in the Texas Lower Plains

Phase II Investigations at Prehistoric and Rock Art Sites, Justiceburg Reservoir, Garza and Kent Counties, Texas Volume I

Phase II cultural resources investigations at the proposed Justiceburg Reservoir in Garza and Kent counties, Texas, were conducted by Prewitt and Associates, Inc. in 19881989. This report documents the archeological work at 62 prehistoric and aboriginal rock art sites and the geoarcheological study conducted as part of the Phase II work. Investigations at 48 prehistoric sites, including open campsites, rockshelters, lithic procurement sites, faunal localities, and rock art sites, resulted in complete National Register assessments; 9 campsites, the 2 rockshelters, and 6 rock art sites are considered to be eligible for listing on the National Register of Historic Places. Less-intensive investigations at 14 prehistoric sites yielded insufficient data for full National Register assessments. The geoarcheological study resulted in the formulation of a model of the geomorphic history of the project area. Of considerable importance is the recognition of a period of catastrophic flushing of alluvial sediments Within the Double Mountain ~ork valley during the middle Holocene, followed by late Holocene sedimentation and stabilization. This supports the concept of a dry middle Holocene Altitherrnal period and helps explain the biased archeological record in the project area. The prehistoric site investigations indicate that most of the archeological remains present at Justiceburg Reservoir date to the late Archaic and Late Prehistoric periods, a phenomenon noted in similar settings elsewhere in the Lower Plains. Of the open campsites assessed as eligible for listing on the National Register, four are classified as late Archaic (4500-2000 B.P.), two are classified as Late Prehistoric I (2000-1000 8.P.), and three are classified as Late Prehistoric II (1000 B.P. to evidence of European contact). The two investigated rockshelters contain evidence of Late Prehistoric I and II occupations. Due to the paucity of regional archeological data and the lack of a well-defined cultural chronology, only two of these sites can be assigned tentatively to recognized cultural complexes. Site 4lGR291 yielded ceramics and arrow points indicating a Palo Duro Complex occupation, ca. A.D. 500, while ceramics and a distinctive hearth associated with the upper component at 41KTS3 suggest a Garza Complex occupation, ca. A.D. 1600-1700. No evidence of European contact was found at any of the habitation sites, but three of the rock art sites contain historic Plains Indian iconography. The investigations at the prehistoric sites resulted in the formulation of a late Holocene cuItural sequence for the project area. Analyses of the various classes of archeological evidence (e.g., artifacts, features, faunal remains) revealed broad cultural patterns that appear to reflect significant changes in subsistence strategies through time. It is suggested that these changes are related to late Holocene environmental conditions and corresponding shifts in the resource base. It is further suggested that bison were the most important resource controlling late Holocene human adaptations in the Texas Lower Plains