The aims of the current study were to describe the extrinsic and intrinsic factors affecting slee... more The aims of the current study were to describe the extrinsic and intrinsic factors affecting sleep in critically ill patients and to examine potential relationships with sleep quality. Sleep was recorded using polysomnography (PSG) and self-reports collected in adult patients in intensive care. Sound and illuminance levels were recorded during sleep recording. Objective sleep quality was quantified using total sleep time divided by the number of sleep periods (PSG sleep period time ratio). A regression model was specified using the "PSG sleep period time ratio" as a dependent variable. Sleep was highly fragmented. Patients rated noise and light as the most sleep disruptive. Continuous equivalent sound levels were 56 dB (A). Median daytime illuminance level was 74 lux, and nighttime levels were 1 lux. The regression model explained 25% of the variance in sleep quality (P = .027); the presence of an artificial airway was the only statistically significant predictor in the model (P = .007). The presence of an artificial airway during sleep monitoring was the only significant predictor in the regression model and may suggest that although potentially uncomfortable, an artificial airway may actually promote sleep. This requires further investigation.
Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains includin... more Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains including those deposited on or beneath soil. Soil can act as a sink for VOCs, causing loading of decomposition VOCs in the soil following soft tissue decomposition. The objective of this study was to chemically profile decomposition VOCs from surface decomposition sites after remains were removed from their primary location. Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS). Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. This study demonstrated that the decomposition VOC profile, while detectable by GC×GC-TOFMS in the soil, was considerably reduced and altered in composition upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.
Challenges in decomposition odour profiling have led to variation in the documented odour profile... more Challenges in decomposition odour profiling have led to variation in the documented odour profile by different research groups worldwide. Background subtraction and use of controls are important considerations given the variation introduced by decomposition studies conducted in different geographical environments. The collection of volatile organic compounds (VOCs) from soil beneath decomposing remains is challenging due to the high levels of inherent soil VOCs, further confounded by the use of highly sensitive instrumentation. This study presents a method that provides suitable chromatographic resolution for profiling decomposition odour in soil by comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry using appropriate controls and field blanks. Logarithmic transformation and t-testing of compounds permitted the generation of a compound list of decomposition VOCs in soil. Principal component analysis demonstrated the improved discrimination between experimental and control soil, verifying the value of the data handling method. Data handling procedures have not been well documented in this field and standardisation would thereby reduce misidentification of VOCs present in the surrounding environment as decomposition byproducts. Uniformity of data handling and instrumental procedures will reduce analytical variation, increasing confidence in the future when investigating the effect of taphonomic variables on the decomposition VOC profile.
ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regard... more ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regarding the decomposition volatile organic compound (VOC) profile of carrion. Validation of this dynamic decomposition VOC profile is required in order to characterise the variables that affect their production. This study was performed to determine whether the decomposition VOC profile produced under field conditions differed between summer and winter in an Australian environment. Outdoor studies were conducted using pig carcasses as human analogues in order to assess seasonal variation in the decomposition process. Common decomposition VOCs were identified using comprehensive two-dimensional gas chromatography – time of flight mass spectrometry (GC×GC-TOFMS). Fewer compounds and reduced abundance of VOCs was observed during winter. Relationships between the levels of detected decomposition VOCs and weather variables were established to be stronger in winter. Weak relationships during summer suggested the potential that an underlying variable (e.g. microbial activity, insect activity) had a stronger relationship to the abundance of decomposition VOCs. The seasonal robustness of the decomposition VOC profile is important to fields relying on the presence of a decomposition odour, i.e. search and recovery of victims in mass disasters, homicides, and missing persons cases.
Purpose Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains ... more Purpose Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains including those deposited on or beneath soil. Soil can act as a sink for VOCs, causing loading of decomposition VOCs in the soil following soft tissue decomposition. The objective of this study was to chemically profile decomposition VOCs from surface decomposition sites after remains were removed from their primary location.
Methods Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC9GC–TOFMS).
Results Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. Conclusions This study demonstrated that the decompo- sition VOC profile, while detectable by GC9GC–TOFMS in the soil, was considerably reduced and altered in com- position upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.
This study evaluates a pilot implementation of the Liverpool Care Pathway (LCP), a clinical tool ... more This study evaluates a pilot implementation of the Liverpool Care Pathway (LCP), a clinical tool used to guide the care of dying patients in the last days of life, on the end-of-life care for dying patients in three regions in rural Australia. The LCP was implemented at 13 participating sites: nine hospitals (general wards), one community-based palliative care service, and three in-hospital palliative care units. To evaluate the implementation of the LCP, 415 eligible patient records were examined: 223 pre-implementation and 192 post-implementation (116 on the LCP and 76 receiving usual care). The primary analysis compared all patients pre-implementation of the LCP versus all patients post-implementation. Increases were found post-implementation for communication with other health professionals and with patients or family (pre-69 %, post-87 %; p ≤ 0.000), use of palliative medications (pre-87 %, post-98 %; p ≤ 0.000) and frequency of symptom assessments (pre-66 %, post-82 %; p ≤ 0.000). Fewer blood and radiological investigations were conducted and venous access devices used in the post-implementation groups than in the pre-implementation period. This study suggests that when rigorously implemented, the LCP improves important components of end-of-life care for dying patients and their families.
In (2), Stanislav Bulygin presents a chosen-ciphertext attack against certain instances of noncom... more In (2), Stanislav Bulygin presents a chosen-ciphertext attack against certain instances of noncommutative polly cracker-type cryptosystems which were proposed in (7) and (9). In this article, we present generalized versions of this attack, which can be used against virtually all polly cracker-type cryp- tosystems. We then present a simple but effective techique to counter these attacks. We also present a
In this paper we consider chosen-ciphertext attacks against non- commutative Polly Cracker-type c... more In this paper we consider chosen-ciphertext attacks against non- commutative Polly Cracker-type cryptosystems. We present several versions of these attacks, as well as techniques to counter them. First we introduce a chosen-ciphertext attack, which assumes a very sim- ple private key. We then present generalizations of this attack which are valid in more general situations, and propose a simple but
ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regard... more ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regarding the decomposition volatile organic compound (VOC) profile of carrion. Validation of this dynamic decomposition VOC profile is required in order to characterise the variables that affect their production. This study was performed to determine whether the decomposition VOC profile produced under field conditions differed between summer and winter in an Australian environment. Outdoor studies were conducted using pig carcasses as human analogues in order to assess seasonal variation in the decomposition process. Common decomposition VOCs were identified using comprehensive two-dimensional gas chromatography – time of flight mass spectrometry (GC×GC-TOFMS). Fewer compounds and reduced abundance of VOCs was observed during winter. Relationships between the levels of detected decomposition VOCs and weather variables were established to be stronger in winter. Weak relationships during summer suggested the potential that an underlying variable (e.g. microbial activity, insect activity) had a stronger relationship to the abundance of decomposition VOCs. The seasonal robustness of the decomposition VOC profile is important to fields relying on the presence of a decomposition odour, i.e. search and recovery of victims in mass disasters, homicides, and missing persons cases.
The aims of the current study were to describe the extrinsic and intrinsic factors affecting slee... more The aims of the current study were to describe the extrinsic and intrinsic factors affecting sleep in critically ill patients and to examine potential relationships with sleep quality. Sleep was recorded using polysomnography (PSG) and self-reports collected in adult patients in intensive care. Sound and illuminance levels were recorded during sleep recording. Objective sleep quality was quantified using total sleep time divided by the number of sleep periods (PSG sleep period time ratio). A regression model was specified using the "PSG sleep period time ratio" as a dependent variable. Sleep was highly fragmented. Patients rated noise and light as the most sleep disruptive. Continuous equivalent sound levels were 56 dB (A). Median daytime illuminance level was 74 lux, and nighttime levels were 1 lux. The regression model explained 25% of the variance in sleep quality (P = .027); the presence of an artificial airway was the only statistically significant predictor in the model (P = .007). The presence of an artificial airway during sleep monitoring was the only significant predictor in the regression model and may suggest that although potentially uncomfortable, an artificial airway may actually promote sleep. This requires further investigation.
the ongoing attrition of the midwifery workforce frustrates future workforce planning and the pro... more the ongoing attrition of the midwifery workforce frustrates future workforce planning and the provision of maternity services in Western Australia. This project determined factors contributing to the intention of the midwives to move jobs and/or leave the profession. a cross-sectional survey approach was taken for this descriptive research utilising a self-administered questionnaire developed by the Nursing and Midwifery Office, Department of Health, Western Australia. public and private health sectors in Western Australia, April-May 2010. 1,600 midwives employed in the public and private health sectors throughout Western Australia were invited to participate: 712 responded (44.5%), one-fifth of the state's registered midwives. most midwives worked part-time in a clinical role in public hospitals. Almost half intended moving jobs within 5 years and/or leaving midwifery. Excluding midwives of retirement age, the most common reasons for intending to move jobs were family commitments, working conditions and role dissatisfaction. Those intending to leave midwifery cited work-life balance, career change and family commitments. Midwives thought addressing the following issues would improve midwifery retention: flexible work arrangements, remuneration, staffing and caseload, workplace culture, professional development and models of care. retaining the midwifery workforce requires attention to workforce practices particularly flexible work arrangements and workloads; models of care to strengthen midwives' relationships with clients and colleagues; and accessible professional development. a review of workplace practices at unit and institution levels is urgently required in Western Australia so that midwives can achieve work-life balance and practice to the full extent of their professional role. These changes are necessary to forestall premature retirement of skilled and experienced midwives from the profession and workforce churn.
The aims of the current study were to describe the extrinsic and intrinsic factors affecting slee... more The aims of the current study were to describe the extrinsic and intrinsic factors affecting sleep in critically ill patients and to examine potential relationships with sleep quality. Sleep was recorded using polysomnography (PSG) and self-reports collected in adult patients in intensive care. Sound and illuminance levels were recorded during sleep recording. Objective sleep quality was quantified using total sleep time divided by the number of sleep periods (PSG sleep period time ratio). A regression model was specified using the "PSG sleep period time ratio" as a dependent variable. Sleep was highly fragmented. Patients rated noise and light as the most sleep disruptive. Continuous equivalent sound levels were 56 dB (A). Median daytime illuminance level was 74 lux, and nighttime levels were 1 lux. The regression model explained 25% of the variance in sleep quality (P = .027); the presence of an artificial airway was the only statistically significant predictor in the model (P = .007). The presence of an artificial airway during sleep monitoring was the only significant predictor in the regression model and may suggest that although potentially uncomfortable, an artificial airway may actually promote sleep. This requires further investigation.
Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains includin... more Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains including those deposited on or beneath soil. Soil can act as a sink for VOCs, causing loading of decomposition VOCs in the soil following soft tissue decomposition. The objective of this study was to chemically profile decomposition VOCs from surface decomposition sites after remains were removed from their primary location. Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS). Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. This study demonstrated that the decomposition VOC profile, while detectable by GC×GC-TOFMS in the soil, was considerably reduced and altered in composition upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.
Challenges in decomposition odour profiling have led to variation in the documented odour profile... more Challenges in decomposition odour profiling have led to variation in the documented odour profile by different research groups worldwide. Background subtraction and use of controls are important considerations given the variation introduced by decomposition studies conducted in different geographical environments. The collection of volatile organic compounds (VOCs) from soil beneath decomposing remains is challenging due to the high levels of inherent soil VOCs, further confounded by the use of highly sensitive instrumentation. This study presents a method that provides suitable chromatographic resolution for profiling decomposition odour in soil by comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry using appropriate controls and field blanks. Logarithmic transformation and t-testing of compounds permitted the generation of a compound list of decomposition VOCs in soil. Principal component analysis demonstrated the improved discrimination between experimental and control soil, verifying the value of the data handling method. Data handling procedures have not been well documented in this field and standardisation would thereby reduce misidentification of VOCs present in the surrounding environment as decomposition byproducts. Uniformity of data handling and instrumental procedures will reduce analytical variation, increasing confidence in the future when investigating the effect of taphonomic variables on the decomposition VOC profile.
ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regard... more ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regarding the decomposition volatile organic compound (VOC) profile of carrion. Validation of this dynamic decomposition VOC profile is required in order to characterise the variables that affect their production. This study was performed to determine whether the decomposition VOC profile produced under field conditions differed between summer and winter in an Australian environment. Outdoor studies were conducted using pig carcasses as human analogues in order to assess seasonal variation in the decomposition process. Common decomposition VOCs were identified using comprehensive two-dimensional gas chromatography – time of flight mass spectrometry (GC×GC-TOFMS). Fewer compounds and reduced abundance of VOCs was observed during winter. Relationships between the levels of detected decomposition VOCs and weather variables were established to be stronger in winter. Weak relationships during summer suggested the potential that an underlying variable (e.g. microbial activity, insect activity) had a stronger relationship to the abundance of decomposition VOCs. The seasonal robustness of the decomposition VOC profile is important to fields relying on the presence of a decomposition odour, i.e. search and recovery of victims in mass disasters, homicides, and missing persons cases.
Purpose Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains ... more Purpose Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains including those deposited on or beneath soil. Soil can act as a sink for VOCs, causing loading of decomposition VOCs in the soil following soft tissue decomposition. The objective of this study was to chemically profile decomposition VOCs from surface decomposition sites after remains were removed from their primary location.
Methods Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC9GC–TOFMS).
Results Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. Conclusions This study demonstrated that the decompo- sition VOC profile, while detectable by GC9GC–TOFMS in the soil, was considerably reduced and altered in com- position upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.
This study evaluates a pilot implementation of the Liverpool Care Pathway (LCP), a clinical tool ... more This study evaluates a pilot implementation of the Liverpool Care Pathway (LCP), a clinical tool used to guide the care of dying patients in the last days of life, on the end-of-life care for dying patients in three regions in rural Australia. The LCP was implemented at 13 participating sites: nine hospitals (general wards), one community-based palliative care service, and three in-hospital palliative care units. To evaluate the implementation of the LCP, 415 eligible patient records were examined: 223 pre-implementation and 192 post-implementation (116 on the LCP and 76 receiving usual care). The primary analysis compared all patients pre-implementation of the LCP versus all patients post-implementation. Increases were found post-implementation for communication with other health professionals and with patients or family (pre-69 %, post-87 %; p ≤ 0.000), use of palliative medications (pre-87 %, post-98 %; p ≤ 0.000) and frequency of symptom assessments (pre-66 %, post-82 %; p ≤ 0.000). Fewer blood and radiological investigations were conducted and venous access devices used in the post-implementation groups than in the pre-implementation period. This study suggests that when rigorously implemented, the LCP improves important components of end-of-life care for dying patients and their families.
In (2), Stanislav Bulygin presents a chosen-ciphertext attack against certain instances of noncom... more In (2), Stanislav Bulygin presents a chosen-ciphertext attack against certain instances of noncommutative polly cracker-type cryptosystems which were proposed in (7) and (9). In this article, we present generalized versions of this attack, which can be used against virtually all polly cracker-type cryp- tosystems. We then present a simple but effective techique to counter these attacks. We also present a
In this paper we consider chosen-ciphertext attacks against non- commutative Polly Cracker-type c... more In this paper we consider chosen-ciphertext attacks against non- commutative Polly Cracker-type cryptosystems. We present several versions of these attacks, as well as techniques to counter them. First we introduce a chosen-ciphertext attack, which assumes a very sim- ple private key. We then present generalizations of this attack which are valid in more general situations, and propose a simple but
ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regard... more ABSTRACT Increased characterisation of decomposition odour has improved existing knowledge regarding the decomposition volatile organic compound (VOC) profile of carrion. Validation of this dynamic decomposition VOC profile is required in order to characterise the variables that affect their production. This study was performed to determine whether the decomposition VOC profile produced under field conditions differed between summer and winter in an Australian environment. Outdoor studies were conducted using pig carcasses as human analogues in order to assess seasonal variation in the decomposition process. Common decomposition VOCs were identified using comprehensive two-dimensional gas chromatography – time of flight mass spectrometry (GC×GC-TOFMS). Fewer compounds and reduced abundance of VOCs was observed during winter. Relationships between the levels of detected decomposition VOCs and weather variables were established to be stronger in winter. Weak relationships during summer suggested the potential that an underlying variable (e.g. microbial activity, insect activity) had a stronger relationship to the abundance of decomposition VOCs. The seasonal robustness of the decomposition VOC profile is important to fields relying on the presence of a decomposition odour, i.e. search and recovery of victims in mass disasters, homicides, and missing persons cases.
The aims of the current study were to describe the extrinsic and intrinsic factors affecting slee... more The aims of the current study were to describe the extrinsic and intrinsic factors affecting sleep in critically ill patients and to examine potential relationships with sleep quality. Sleep was recorded using polysomnography (PSG) and self-reports collected in adult patients in intensive care. Sound and illuminance levels were recorded during sleep recording. Objective sleep quality was quantified using total sleep time divided by the number of sleep periods (PSG sleep period time ratio). A regression model was specified using the "PSG sleep period time ratio" as a dependent variable. Sleep was highly fragmented. Patients rated noise and light as the most sleep disruptive. Continuous equivalent sound levels were 56 dB (A). Median daytime illuminance level was 74 lux, and nighttime levels were 1 lux. The regression model explained 25% of the variance in sleep quality (P = .027); the presence of an artificial airway was the only statistically significant predictor in the model (P = .007). The presence of an artificial airway during sleep monitoring was the only significant predictor in the regression model and may suggest that although potentially uncomfortable, an artificial airway may actually promote sleep. This requires further investigation.
the ongoing attrition of the midwifery workforce frustrates future workforce planning and the pro... more the ongoing attrition of the midwifery workforce frustrates future workforce planning and the provision of maternity services in Western Australia. This project determined factors contributing to the intention of the midwives to move jobs and/or leave the profession. a cross-sectional survey approach was taken for this descriptive research utilising a self-administered questionnaire developed by the Nursing and Midwifery Office, Department of Health, Western Australia. public and private health sectors in Western Australia, April-May 2010. 1,600 midwives employed in the public and private health sectors throughout Western Australia were invited to participate: 712 responded (44.5%), one-fifth of the state's registered midwives. most midwives worked part-time in a clinical role in public hospitals. Almost half intended moving jobs within 5 years and/or leaving midwifery. Excluding midwives of retirement age, the most common reasons for intending to move jobs were family commitments, working conditions and role dissatisfaction. Those intending to leave midwifery cited work-life balance, career change and family commitments. Midwives thought addressing the following issues would improve midwifery retention: flexible work arrangements, remuneration, staffing and caseload, workplace culture, professional development and models of care. retaining the midwifery workforce requires attention to workforce practices particularly flexible work arrangements and workloads; models of care to strengthen midwives' relationships with clients and colleagues; and accessible professional development. a review of workplace practices at unit and institution levels is urgently required in Western Australia so that midwives can achieve work-life balance and practice to the full extent of their professional role. These changes are necessary to forestall premature retirement of skilled and experienced midwives from the profession and workforce churn.
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Papers by Tapan Rai
Methods Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC9GC–TOFMS).
Results Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. Conclusions This study demonstrated that the decompo- sition VOC profile, while detectable by GC9GC–TOFMS in the soil, was considerably reduced and altered in com- position upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.
Methods Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC9GC–TOFMS).
Results Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. Conclusions This study demonstrated that the decompo- sition VOC profile, while detectable by GC9GC–TOFMS in the soil, was considerably reduced and altered in com- position upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.