478 research outputs found
The Impact of Careers Guidance for Employed Adults in Continuing Education
The validity of the matching estimator in programme evaluation depends on the completeness of the set of variables used for matching. When an attitudinal variable is relevant for the participation decision, but is either unmeasured or measured only after entry to the programme, estimates of effects may be biased or hard to interpret. This issue is investigated with data from an evaluation study of careers guidance for employed adults, which utilised the method of propensity score matching. Job satisfaction, measured shortly after entry to the programme, was found to be strongly associated with participa-tion, but may itself have been influenced by the early experience of careers guidance. Estimates of the impacts of guidance on several post-programme education and training outcomes are considered, both including and exclud-ing the job satisfaction measure from the participation model. Data experiments with adjusted values of job satisfaction are also performed. It is found that estimates of treatment effects are highly sensitive to these variants, and respond in a non-monotonic fashion. The implications for evaluation methodology are discussed.
Microscopy, Surfaces and the Unknowable in Seventeenth Century Natural Philosophy (from Lucretius to Margaret Cavendish)
Cedar 88
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94656/1/eost7523.pd
Restructuring the southside for innovation: technology, education, and holistic job growth in Danville, Virginia
Like many mid-sized Piedmont manufacturing towns, Danville Virginia was hit hard by the wave of out-sourcing which swept the United States from the 1980s through the early years of the current century. With an economy disabled by the decline of textile and tobacco production, Danville faced serious losses in jobs and an increasing threat of economic devastation to the city (Breaux, 2000). Regionally isolated in the south of Virginia, Danville is closer to Charlotte than to Richmond, two hours from Blacksburg, and about an hour and a half from the Research Triangle. It is a town known well for its "Millionaires Row," where dazzling 19th century mansions tell the flamboyant story of the city's once booming economy. While the mansions have been lovingly cared for in many cases, homes in many of the neighborhoods relate the story of the town's decline in recent years. Educational achievement in particular expresses the local disinvestment in workforce capacity due to decades of reliance on a pair of industries that needed little preparation from their workers. In 2000, adults over 25 years of age in the Danville region were significantly underperforming by statewide standards: 67.9% had graduated from high school, as compared with 81.5% statewide; 11.6% had bachelor's degrees, almost a third of the 29.5% statewide estimate; median household income was also low at 50,028 (Franklin 2008). The previous year an estimated 20% of individuals lived below the poverty line while 9.6% statewide did. In the past decade, the Institute for Advanced Learning and Research has aimed at correcting some of these ills. The main interest of this qualitative study is to determine whether the Institute is by itself an answer to the employment/economic development problems faced by the town. How does the organization address barriers to inclusion for incumbent workers? Will its programs really replace the old manufacturing sector? Danville is not a unique case in its post-manufacturing malaise, of course. It is joined by numerous Piedmont towns and cities in Virginia and North Carolina (which is less than five miles' drive away) that have seen these industries drawn away to cheaper labor markets around the world while the local economies have declined. In Virginia, University-based programs like those at James Madison University have been supporting growth of bio sciences in the northern part of the state. The Virginia Biotechnology Association, based in Richmond, serves to connect the various statewide biotech programs and advocate on their behalf to the state legislature. But in the Southside, there is a dearth of universities to begin with. Those that do exist are in Roanoke, Blacksburg, and Danville. In Virginia, there are currently 82 biotechnology firms, 64% of which are located in Richmond or points north (VABIO, 2010).The Western area of the state, which here includes the Danville region, represents about 14% of the total. The Southside, overall, is the least represented in this. Danville is currently home to one private biotech company, Luna Nanotechnology, whose headquarters are in BlacksburgMaster of City and Regional Plannin
Impregnating hessian strips with the volatile pyrethroid transfluthrin prevents outdoor exposure to vectors of malaria and lymphatic filariasis in urban Dar es Salaam, Tanzania
Background
Semi-field trials using laboratory-reared Anopheles arabiensis have shown that, delivering the volatile pyrethroid transfluthrin by absorption into hessian strips, consistently provided > 99 % human protective efficacy against bites for 6 months without retreating. Here the impact of this approach upon human exposure to wild populations of vectors for both malaria and filariasis under full field conditions is assessed for the first time.
Methods
Transfluthrin-treated and untreated strips were placed around human volunteers conducting human landing catch in an outdoor environment in urban Dar es Salaam, where much human exposure to malaria and filariasis transmission occurs outdoors. The experiment was replicated 9 times at 16 outdoor catching stations in 4 distinct locations over 72 working nights between May and August 2012.
Results
Overall, the treated hessian strips conferred 99 % protection against An. gambiae (1 bite versus 159) and 92 % protection against Culex spp. (1478 bites versus 18,602). No decline in efficacy over the course of the study could be detected for the very sparse populations of An. gambiae (P = 0.32) and only a slow efficacy decline was observed for Culex spp. (P < 0.001), with protection remaining satisfactory over 3 months after strip treatment. Diversion of mosquitoes to unprotected humans in nearby houses was neither detected for An. gambiae (P = 0.152) nor for Culex spp. (Relative rate, [95 % CI] = 1.03, [0.95, 1.11], P = 0.499).
Conclusion
While this study raises more questions than it answers, the presented evidence of high protection over long periods suggest this technology may have potential for preventing outdoor transmission of malaria, lymphatic filariasis and other vector-borne pathogens
Consistently high estimates for the proportion of human exposure to malaria vector populations occurring indoors in rural Africa.
BACKGROUND: Insecticide-treated nets (ITNs) and indoor residual spraying (IRS) are highly effective tools for controlling malaria transmission in Africa because the most important vectors, from the Anopheles gambiae complex and the A. funestus group, usually prefer biting humans indoors at night. METHODS: Matched surveys of mosquito and human behaviour from six rural sites in Burkina Faso, Tanzania, Zambia, and Kenya, with ITN use ranging from 0.2% to 82.5%, were used to calculate the proportion of human exposure to An. gambiae sensu lato and An. funestus s.l. that occurs indoors (Ï€i), as an indicator of the upper limit of personal protection that indoor vector control measures can provide. This quantity was also estimated through use of a simplified binary analysis (Ï€(i)(B)) so that the proportions of mosquitoes caught indoors (Pi), and between the first and last hours at which most people are indoors (Pfl) could also be calculated as underlying indicators of feeding by mosquitoes indoors or at night, respectively. RESULTS: The vast majority of human exposure to Anopheles bites occurred indoors (Ï€(i)(B)= 0.79-1.00). Neither An. gambiae s.l. nor An. funestus s.l. strongly preferred feeding indoors (P(i) = 0.40-0.63 and 0.22-0.69, respectively), but they overwhelmingly preferred feeding at times when most humans were indoors (P(fl) = 0.78-1.00 and 0.86-1.00, respectively). CONCLUSIONS: These quantitative summaries of behavioural interactions between humans and mosquitoes constitute a remarkably consistent benchmark with which future observations of vector behaviour can be compared. Longitudinal monitoring of these quantities is vital to evaluate the effectiveness of ITNs and IRS and the need for complementary measures that target vectors outdoors
An improved mosquito electrocuting trap that safely reproduces epidemiologically relevant metrics of mosquito human-feeding behaviours as determined by human landing catch
Background:
Reliable quantification of mosquito host—seeking behaviours is required to determine the efficacy of vector control methods. For malaria, the gold standard approach remains the risky human landing catch (HLC). Here compare the performance of an improved prototype of the mosquito electrocuting grid trap (MET) as a safer alternative with HLC for measuring malaria vector behaviour in Dar es Salaam, Tanzania.
Methods:
Mosquito trapping was conducted at three sites within Dar es Salaam representing a range of urbanicity over a 7-month period (December 2012–July 2013, 168 sampling nights). At each site, sampling was conducted in a block of four houses, with two houses being allocated to HLC and the other to MET on each night of study. Sampling was conducted both indoors and outdoors (from 19:00 to 06:00 each night) at all houses, with trapping method (HLC and MET) being exchanged between pairs of houses at each site using a crossover design.
Results:
The MET caught significantly more Anopheles gambiae sensu lato than the HLC, both indoors (RR [95 % confidence interval (CI)]) = 1.47 [1.23–1.76], P < 0.0001 and outdoors = 1.38 [1.14–1.67], P < 0.0001). The sensitivity of MET compared with HLC did not detectably change over the course of night for either An. gambiae s.l. (OR [CI]) = 1.01 [0.94–1.02], P = 0.27) or Culex spp. (OR [CI]) = 0.99 [0.99–1.0], P = 0.17) indoors and declined only slightly outdoors: An. gambiae s.l. (OR [CI]) = 0.92 [0.86–0.99], P = 0.04), and Culex spp. (OR [CI]) = 0.99 [0.98–0.99], P = 0.03). MET-based estimates of the proportions of mosquitoes caught indoors (P i ) or during sleeping hours (P fl ), as well as the proportion of human exposure to bites that would otherwise occurs indoors (π i ), were statistically indistinguishable from those based on HLC for An. gambiae s.l. (P = 0.43, 0.07 and 0.48, respectively) and Culex spp. (P = 0.76, 0.24 and 0.55, respectively).
Conclusions:
This improved MET prototype is highly sensitive tool that accurately quantifies epidemiologically-relevant metrics of mosquito biting densities, behaviours and human exposure distribution
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