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The infestation of the fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in Africa since 2016 has been a major threat to maize production. Previous studies in Togo and Ghana from 2016 to 2018 did not correlate FAW infestation to yield losses. Thus, the aim of this study which assesses the impact of FAW infestation by inspecting 150 maize farms throughout the five Agro-Ecological Zones (AEZs) of Togo for FAW plant damage, and third instar larvae were used to infest 10-day-old maize plants in netted plots under controlled conditions at an experiment station (Station d'Expérimentations Agronomiques de Lomé) in 2019 and 2020. As control plots at the experiment station, plots were both netted and treated with emamectin benzoate, simply netted, or open to natural infestation. The number of larvae, egg masses, percent damaged plants, and damage proportions of leaves and ears were scored until harvest. Infestations and damages on maize plant throughout Togo were similar between the two years but were higher in the southern part of the county (AEZ5). At the experiment station, the yield losses were significantly considerable and increased from 25% infestation. The losses were 0.37 t ha−1 for 25% infestation, 0.34 t ha−1 for 30%, 0.59 t ha−1 for the open plots, 0.70 t ha−1 for simple netted and 50% infestation, 1.03 t ha−1 for 75%, and 1.27 t ha−1 for 100% infestation. This current study suggested thorough inspection on maize farms to set off management practices from 25% of infestation.
To compare strategies for hospital ranking based on colon surgical-site infection (SSI) rate by combining all colon procedures versus stratifying by surgical approach (ie, laparoscopic vs open).
Retrospective cohort study.
We identified SSIs among Medicare beneficiaries undergoing colon surgery from 2009 through 2013 using previously validated methods. We created a risk prediction model for SSI using age, sex, race, comorbidities, surgical approach (laparoscopy vs open), and concomitant colon and noncolon procedures. Adjusted SSI rates were used to rank hospitals. Subanalyses were performed for common colon procedures and procedure types for which there were both open and laparoscopic procedures. We generated ranks using only open and only laparoscopic procedures, overall and for each subanalysis. Rankings were compared using a Spearman correlation coefficient.
In total, 694,813 colon procedures were identified among 508,135 Medicare beneficiaries. The overall SSI rate was 7.6%. The laparoscopic approach was associated with lower SSI risk (OR, 0.5; 95% CI, 0.4–0.5), and higher SSI risk was associated with concomitant abdominal surgeries (OR, 1.4; 95% CI, 1.4–1.5) and higher Elixhauser score (OR, 1.1; 95% CI, 1.0–1.1). Hospital rankings for laparascopic procedures were poorly correlated with rankings for open procedures (r = 0.23).
Hospital rankings based on total colon procedures fail to account for differences in SSI risk from laparoscopic vs open procedures. Stratifying rankings by surgical approach yields a more equitable comparison of surgical performance.
From 2014 to 2020, we compiled radiocarbon ages from the lower 48 states, creating a database of more than 100,000 archaeological, geological, and paleontological ages that will be freely available to researchers through the Canadian Archaeological Radiocarbon Database. Here, we discuss the process used to compile ages, general characteristics of the database, and lessons learned from this exercise in “big data” compilation.
The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
Clostridioides difficile infection (CDI) causes significant morbidity and mortality; however, the diagnosis of CDI remains controversial. The primary aim of our study was to evaluate the association of polymerase chain reaction (PCR) cycle threshold (Ct) values with CDI disease severity, recurrence, and mortality among adult patients with CDI.
Retrospective cohort study.
Single tertiary-care hospital.
Adult patients diagnosed with hospital-onset, healthcare facility–associated CDI from June 2014 to September 2015.
We performed a retrospective chart review of included patients. Univariate and multivariable logistic regression methods were used to evaluate the association between Ct values and CDI severity, 8-week recurrence, and 30-day mortality.
Among 318 included patients, 51% were male and the mean age was 62 years; ~32% of the patients developed severe CDI and 11% developed severe–complicated CDI. The 30-day all-cause mortality rate was 11% and the 8-week recurrence rate was 9.5%. The overall mean Ct value was 32.9 (range, 23–40). Multivariable analyses showed that lower values of PCR Ct were associated with increased odds of 30-day morality (odds ratio [OR] 0.83; 95% confidence interval [CI], 0.72–0.96) but were not independently associated with CDI severity (OR, 0.99; 95% CI, 0.90–1.09) or recurrence (OR, 0.88; 95% CI, 0.77–1.00).
Our findings suggest that PCR Ct values at the time of diagnosis may have a limited predictive value and utility in clinical decision making for inpatients with CDI. Larger, prospective studies across different patient populations are needed to confirm our findings.
Providing care for people with behavioural and psychological symptoms of dementia is stressful as these individuals are commonly labelled as aggressive or resistant to care. Few studies have evaluated the impact of providing support to professional caregivers working in long-term care. Our mixed methods pilot study evaluated the impact of the innovative Affect Education Model among health care providers from two Toronto nursing homes.
The two-person centred Affect Educational Model through the use of seven questions that encourage self-reflection teaches that problematic behaviours are co-constructed between individuals with BPSD and caregivers. Study procedures included recruiting nursing staff and personal support workers and teaching them the model in five weekly 30-minute group sessions. Qualitative measures in the form of focus groups were obtained. Quantitative measures were obtained through the use of five questionnaires.
Qualitative findings from focus groups identified four themes: facilitators and barriers perceived in current care delivery, the impact of the model experience on staff care delivery, reflections on being taught the model, and future model implementation. Quantitative results were also collected and discussed.
The use of both pharmacologic and nonpharmacologic treatment of individuals with BPSD may be greatly enhanced by an interpersonal two-person Affect Education Model that emphasizes the importance of calming down and self-reflection. Future directions include expanding the model to family caregivers through the use of multimedia resources.
Responsive behaviours in dementia are associated with poor outcomes for the person with dementia (PWD) and caregiver burnout. Family caregivers need a variety of tools to manage responsive behaviours. The Baycrest Quick-Response Caregiver Tool was developed to provide caregivers with a tool that can be used in real time. In this study, the feasibility, impact, and effectiveness of this new tool were studied in family caregivers and health care providers (HCP) using quantitative and qualitative measures.
Family caregivers were recruited and were asked to complete a pre-survey before being sent the link to the educational tool. One month after the telephone survey, caregivers were sent an online post-survey to gather their feedback on the tool and the impact of the tool on caregiver well -being. Healthcare providers were also recruited and reviewed the tool through an online feedback survey. The feasibility, impact, and effectiveness of the tool were assessed using quantitative and qualitative measures.
Caregivers had a moderate degree of and reported a high level of competence - these scores were maintained throughout the study. Caregivers reported that tool positively impacted their compassion towards the person with dementia (PWD), and that their interactions with improved. 100% of HCP who completed the feedback survey would recommend the tool to other HCP and to caregivers of PWD. The caregivers and HCP provided specific suggestions for improvement.
The Baycrest Quick-Response Caregiver Tool was found to be feasible and helpful. It provides caregivers and HCP with an additional approach for responsive behaviours.
Background: Shared Healthcare Intervention to Eliminate Life-threatening Dissemination of MDROs in Orange County, California (SHIELD OC) was a CDC-funded regional decolonization intervention from April 2017 through July 2019 involving 38 hospitals, nursing homes (NHs), and long-term acute-care hospitals (LTACHs) to reduce MDROs. Decolonization in NH and LTACHs consisted of universal antiseptic bathing with chlorhexidine (CHG) for routine bathing and showering plus nasal iodophor decolonization (Monday through Friday, twice daily every other week). Hospitals used universal CHG in ICUs and provided daily CHG and nasal iodophor to patients in contact precautions. We sought to evaluate whether decolonization reduced hospitalization and associated healthcare costs due to infections among residents of NHs participating in SHIELD compared to nonparticipating NHs. Methods: Medicaid insurer data covering NH residents in Orange County were used to calculate hospitalization rates due to a primary diagnosis of infection (counts per member quarter), hospital bed days/member-quarter, and expenditures/member quarter from the fourth quarter of 2015 to the second quarter of 2019. We used a time-series design and a segmented regression analysis to evaluate changes attributable to the SHIELD OC intervention among participating and nonparticipating NHs. Results: Across the SHIELD OC intervention period, intervention NHs experienced a 44% decrease in hospitalization rates, a 43% decrease in hospital bed days, and a 53% decrease in Medicaid expenditures when comparing the last quarter of the intervention to the baseline period (Fig. 1). These data translated to a significant downward slope, with a reduction of 4% per quarter in hospital admissions due to infection (P < .001), a reduction of 7% per quarter in hospitalization days due to infection (P < .001), and a reduction of 9% per quarter in Medicaid expenditures (P = .019) per NH resident. Conclusions: The universal CHG bathing and nasal decolonization intervention adopted by NHs in the SHIELD OC collaborative resulted in large, meaningful reductions in hospitalization events, hospitalization days, and healthcare expenditures among Medicaid-insured NH residents. The findings led CalOptima, the Medicaid provider in Orange County, California, to launch an NH incentive program that provides dedicated training and covers the cost of CHG and nasal iodophor for OC NHs that enroll.
Disclosures: Gabrielle M. Gussin, University of California, Irvine, Stryker (Sage Products): Conducting studies in which contributed antiseptic product is provided to participating hospitals and nursing homes. Clorox: Conducting studies in which contributed antiseptic product is provided to participating hospitals and nursing homes. Medline: Conducting studies in which contributed antiseptic product is provided to participating hospitals and nursing homes. Xttrium: Conducting studies in which contributed antiseptic product is provided to participating hospitals and nursing homes.
We describe an ultra-wide-bandwidth, low-frequency receiver recently installed on the Parkes radio telescope. The receiver system provides continuous frequency coverage from 704 to 4032 MHz. For much of the band (
), the system temperature is approximately 22 K and the receiver system remains in a linear regime even in the presence of strong mobile phone transmissions. We discuss the scientific and technical aspects of the new receiver, including its astronomical objectives, as well as the feed, receiver, digitiser, and signal processor design. We describe the pipeline routines that form the archive-ready data products and how those data files can be accessed from the archives. The system performance is quantified, including the system noise and linearity, beam shape, antenna efficiency, polarisation calibration, and timing stability.
As the IAU heads towards its second century, many changes have simultaneously transformed Astronomy and the human condition world-wide. Amid the amazing recent discoveries of exoplanets, primeval galaxies, and gravitational radiation, the human condition on Earth has become blazingly interconnected, yet beset with ever-increasing problems of over-population, pollution, and never-ending wars. Fossil-fueled global climate change has begun to yield perilous consequences. And the displacement of people from war-torn nations has reached levels not seen since World War II.
Extracorporeal membrane oxygenation within CPR (ECPR) may improve survival for refractory out-of-hospital cardiac arrest (OHCA). We developed a prehospital, emergency department (ED), and hospital-based clinical and educational protocol to improve the key variable of time-to-ECPR (TTE).
In a single urban health region we involved key prehospital, clinical, and administrative stakeholders over a 2-year period, to develop a regional ECPR program with destination to a single urban tertiary care hospital. We developed clear and reproducible inclusion criteria and processes, including measures of program efficiency. We conducted seminars and teaching modules to paramedics and hospital-based clinicians including monthly simulator sessions, and performed detailed reviews of each treated case in the form of report cards. In this before-and-after study we compared patients with ECPR attempted prior to, and after, protocol implementation. The primary outcome was TTE, defined as the time of initial professional CPR to establishment of extracorporeal circulation. We compared the median TTE for patients in the two groups using the Wilcoxon signed rank test.
Four patients were identified prior to the protocol and managed in an ad hoc basis; for nine patients the protocol was utilized. Overall favourable neurological outcomes among ECPR-treated patients were 27%. The median TTE was 136 minutes (IQR 98 - 196) in the pre-protocol group, and 60 minutes (IQR 49 - 81) minutes in the protocol group (p=0.0165).
An organized clinical and educational protocol to initiate ECPR for patients with OHCA is feasible and significantly reduces the key benchmark of time-to-ECPR flows.
Field experiments were conducted from 1986 to 1988 at Lacombe and Lethbridge, Alberta and Scott, Saskatchewan to determine growth and yield response of canola to mixtures of ethametsulfuron with specific grass herbicides. Ethametsulfuron did not usually cause canola injury when mixed with sethoxydim. However, ethametsulfuron mixtures with the following grass herbicides listed in decreasing order of injury potential, often caused canola injury and yield loss: haloxyfop > fluazifop > fluazifop-P > quizalofop > quizalofop-P. Canola yield losses were severe in some experiments, ranging from 59% with quizalofop mixtures to 97% with haloxyfop mixtures; in other experiments, the same mixtures did not cause significant yield losses. ‘Tobin,’ a Brassica rapa cultivar, tended to be more susceptible to injury than the B. napus cultivars ‘Pivot’ and ‘Westar.’ Canola injury symptoms were consistent with those expected from sulfonylurea herbicides. Therefore, we suggest that specific grass herbicides differentially impair the ability of canola to metabolize ethametsulfuron to inactive forms.
Wild radish is a prevalent annual weed throughout the cropping regions of southern Australia. Field experiments were conducted at Wagga Wagga, New South Wales, in 1998 and 1999 to determine the effect of various densities and emergence times of wild radish on yield and quality of canola and on wild radish seed production. As few as 4 wild radish m−2 emerging with canola reduced canola yield 9 to 11%, whereas 64 wild radish m−2 reduced canola yield 77 to 91%. Wild radish interference in canola was greatly affected by its time of emergence relative to canola. At 64 wild radish m−2, canola yield was reduced 77, 54, 33, and 19% in 1998 and 91, 65, 56, and 19% in 1999 when wild radish emerged 0, 2, 4, and 7 wk after canola, respectively. Wild radish that emerged 10 wk after canola did not reduce canola yield. Maximum wild radish seed production ranged from 24,183 to 32,167 seed m−2 when they emerged with canola at high densities. Wild radish that emerged later than canola produced much less seed, but some seed production still occurred in one of the 2 yr when it emerged as late as 10 wk after canola. Wild radish did not directly reduce canola quality in either year, but if wild radish seed were not separated from canola seed, the amount of erucic acid and glucosinolates was increased above marketable levels in some cases. The results of this study will be used to advise growers on wild radish control in canola and will aid the development of a multiyear management strategy for this troublesome weed in annual cropping systems.
As a weed, wheat has recently gained greater profile. Determining wheat persistence in cropping systems will facilitate the development of effective volunteer wheat management strategies. In October of 2000, glyphosate-resistant (GR) spring wheat seeds were scattered on plots at eight western Canada sites. From 2001 to 2003, the plots were seeded to a canola–barley–field-pea rotation or a fallow–barley–fallow rotation, with five seeding systems involving seeding dates and soil disturbance levels, and monitored for wheat plant density. Herbicides and tillage (in fallow systems) were used to ensure that no wheat plants produced seed. Seeding systems with greater levels of soil disturbance usually had greater wheat densities. Volunteer wheat densities at 2 (2002) and 3 (2003) yr after seed dispersal were close to zero but still detectable at most locations. At the end of 2003, viable wheat seeds were not detected in the soil seed bank at any location. The majority of wheat seedlings were recruited in the year following seed dispersal (2001) at the in-crop, prespray (PRES) interval. At the PRES interval in 2001, across all locations and treatments, wheat density averaged 2.6 plants m−2. At the preplanting interval (PREP), overall wheat density averaged only 0.2 plants m−2. By restricting density data to include only continuous cropping, low-disturbance direct-seeding (LDS) systems, the latter mean dropped below 0.1 plants m−2. Only at one site were preplanting GR wheat densities sufficient (4.2 plants m−2) to justify a preseeding herbicide treatment in addition to glyphosate in LDS systems. Overall volunteer wheat recruitment at all spring and summer intervals in the continuous cropping rotation in 2001 was 1.7% (3.3 plants m−2). Despite the fact that volunteer wheat has become more common in the central and northern Great Plains, there is little evidence from this study to suggest that its persistence will be a major agronomic problem.
The discovery of Heusler alloys has revolutionized the research field of intermetallics due to the ease with which one can derive potential candidates for multifunctional applications. During recent years, many half Heusler alloys have been investigated for their thermoelectric properties. The f-electron-based rare-earth ternary half Heusler compound DyPdBi has its f energy levels located close to the Fermi energy level. Other research efforts have emphasized that such materials have good thermoelectric capabilities. We have explored using first principles the electronic band structure of DyPdBi by use of different exchange correlation potentials in the density functional theoretical framework. Transport coefficients that arise in the study of thermoelectric properties of DyPdBi have been calculated and have illustrated its potential as an efficient thermoelectric material. Both the theoretically estimated Seebeck coefficient and the power factor agree well with the available experimental results. Our calculations illustrate that it is essential to include spin–orbit coupling in these models of f-electron half Heusler materials.
Hybrid solar receivers utilizing both photovoltaic cells and thermal collectors are capable of collecting the entire solar spectrum for use in energy systems. Such systems provide efficient solar energy conversion using PV in addition to dispatchability through thermal storage by incorporating a thermal collector in conjunction with the PV. Proposed hybrid systems typically invoke spectrum splitting so to redirect photons optimized for PV electric conversion to a cell while non-PV efficient photons are directed to a thermal absorber. This work discusses a hybrid system with a selective solar filter using a suspended nanoparticle fluid to directly absorb non-PV photons. Non-absorbed photons pass through the filter and impact the PV. Choice of nanoparticles in the fluid allow absorption and transmission of specific wavelengths. Nanoparticles were chosen based on optimization simulations for a bandpass filter to a cSi solar cell. The synthesized fluid has been experimentally characterized to show the effects of high temperature on nanoparticle stability and optical properties. Thermodynamic modeling of the system suggests solar to electric efficiency of the total system is 23.2% if all thermal energy is converted to electricity through an organic Rankine cycle (ORC). However, high temperature generation could be used for industrial process heat at a specific temperature by changing parameters such as absorbed energy and flow rates. Furthermore, a prototype is being developed with 14x concentration to demonstrate the technology on-sun with initial testing targeted for the 2nd quarter of 2016. Overall, the hybrid nanoparticle filter concentrating solar collector can be modified to fit a variety of applications through easily changeable parameters in the system.
The two Pan-STARRS telescopes, located on Haleakala, Maui, Hawaii, are 1.8-meter diameter telescopes equipped with 1.4 Gigapixel cameras that deliver 7 square degree fields-of-view. The first of these telescopes, Pan-STARRS1, is conducting a search for Near Earth Objects, and is currently the leading discoverer of Near Earth Objects. The second telescope, Pan-STARRS2, is nearing the end of its commissioning, and is becoming more productive.
Pan-STARRS has become the leading survey for Near Earth Objects, responsible for approximately half of the NEO discoveries to date in 2015. Pan-STARRS is also the leading discoverer of new comets.