13,773 research outputs found
Subject index and checklist of history and archaeology dissertations and research essays submitted at the University of Botswana, 1976 - 1998
Four MA dissertations and 222 BA research essays are listed alphabetically, and indexed by reference number under three subject categories-geographical area (by district, etc.), ethnic group, and a general subject index of 42 headings. All but 31 of the 226 alphabetical entries contain research solely on Botswana: the other countries being South Africa (12 entries), Zimbabwe (11), Namibia (6), Angola and Zambia (1 each). The most researched district of Botswana is Central (54 entries), followed by Kgatleng and Kweneng (25 each), North-East (24), South-East (16), Southern (9), Ngamiland (6), Chobe and Ghanzi (3 each), and Kgalagadi (2). The subject index of 29 ethnic groups ranges from Afrikaners (2 entries) and Amandebele (2) through Babirwa (7), Bakalanga (24), Bakgatla (27), Bakhalagari (4), Bakwena (21), Bangwato (19), Basarwa (5), and Batlharo (1), to Indians (3) and Ovambanderu (2). The general subject index ranges from Administration (29 entries), Agriculture (18), and Archaeology (21), through Biography (28), Cattle (7), Chieftainship (27), Class formation (7), Councils (7), Economic development (23), Education (14), and Heritage management (7), to Labour and labour migration (7), Medicine (4), Nationalism (13), Religion (15), Serfdom, servitude and slavery (7), Settlement history (19), Trade and commerce (13), Trade unions (6), and Urbanization (15). With the notable exception of one MA dissertation, there is a lack of cultural studies which may partly be attributed to research being done instead under the aegis of other departments in the Faculty of Humanities
Elevated pCO2 enhances bacterioplankton removal of organic carbon.
Factors that affect the removal of organic carbon by heterotrophic bacterioplankton can impact the rate and magnitude of organic carbon loss in the ocean through the conversion of a portion of consumed organic carbon to CO2. Through enhanced rates of consumption, surface bacterioplankton communities can also reduce the amount of dissolved organic carbon (DOC) available for export from the surface ocean. The present study investigated the direct effects of elevated pCO2 on bacterioplankton removal of several forms of DOC ranging from glucose to complex phytoplankton exudate and lysate, and naturally occurring DOC. Elevated pCO2 (1000-1500 ppm) enhanced both the rate and magnitude of organic carbon removal by bacterioplankton communities compared to low (pre-industrial and ambient) pCO2 (250 -~400 ppm). The increased removal was largely due to enhanced respiration, rather than enhanced production of bacterioplankton biomass. The results suggest that elevated pCO2 can increase DOC consumption and decrease bacterioplankton growth efficiency, ultimately decreasing the amount of DOC available for vertical export and increasing the production of CO2 in the surface ocean
Unique Thermal Properties of Clothing Materials.
Cloth wearing seems so natural that everyone is self-deemed knowledgeable and has some expert opinions about it. However, to clearly explain the physics involved, and hence to make predictions for clothing design or selection, it turns out to be quite challenging even for experts. Cloth is a multiphased, porous, and anisotropic material system and usually in multilayers. The human body acts as an internal heat source in a clothing situation, thus forming a temperature gradient between body and ambient. But unlike ordinary engineering heat transfer problems, the sign of this gradient often changes as the ambient temperature varies. The human body also perspires and the sweat evaporates, an effective body cooling process via phase change. To bring all the variables into analysis quickly escalates into a formidable task. This work attempts to unravel the problem from a physics perspective, focusing on a few rarely noticed yet critically important mechanisms involved so as to offer a clearer and more accurate depiction of the principles in clothing thermal comfort
Rewiring strategies for changing environments
A typical pervasive application executes in a changing environment: people, computing resources, software services and network connections come and go continuously. A robust pervasive application needs adapt to this changing context as long as there is an appropriate rewiring strategy that guarantees correct behavior. We combine the MERODE modeling methodology with the ReWiRe framework for creating interactive pervasive applications that can cope with changing environments. The core of our approach is a consistent environment model, which is essential to create (re)configurable context-aware pervasive applications. We aggregate different ontologies that provide the required semantics to describe almost any target environment. We present a case study that shows a interactive pervasive application for media access that incorporates parental control on media content and can migrate between devices. The application builds upon models of the run-time environment represented as system states for dedicated rewiring strategies
Effectiveness and safety of cemented and uncemented hemiarthroplasty for the treatment of intracapsular hip fractures:a systematic review and meta-analysis of randomised controlled trials
Aims
We conducted a systematic review and meta-analysis to compare the mortality, morbidity, and functional outcomes of cemented versus uncemented hemiarthroplasty in the treatment of intracapsular hip fractures, analyzing contemporary and non-contemporary implants separately.
Methods
PubMed, Medline, EMBASE, CINAHL, and Cochrane Library were searched to 2 February 2020 for randomized controlled trials (RCTs) comparing the primary outcome, mortality, and secondary outcomes of function, quality of life, reoperation, postoperative complications, perioperative outcomes, pain, and length of hospital stay. Relative risks (RRs) and mean differences (with 95% confidence intervals (CIs)) were used as summary association measures.
Results
A total of 18 studies corresponding to 16 non-overlapping RCTs with a total of 2,819 intracapsular hip fractures were included. Comparing contemporary cemented versus uncemented hemiarthroplasty, RRs (95% CIs) for mortality were 1.32 (0.44 to 3.99) perioperatively, 1.01 (0.48 to 2.10) at 30 days, and 0.90 (0.71 to 1.15) at one year. The use of contemporary cemented hemiarthroplasty reduced the risk of intra- and postoperative periprosthetic fracture. There were no significant differences in the risk of other complications, function, pain, and quality of life. There were no significant differences in perioperative outcomes except for increases in operating time and overall anaesthesia for contemporary cemented hemiarthroplasty with mean differences (95% CIs) of 6.67 (2.65 to 10.68) and 4.90 (2.02 to 7.78) minutes, respectively. The morbidity and mortality outcomes were not significantly different between non-contemporary cemented and uncemented hemiarthroplasty.
Conclusion
There are no differences in the risk of mortality when comparing the use of contemporary cemented with uncemented hemiarthroplasty in the management of intracapsular hip fractures. Contemporary cemented hemiarthroplasty is associated with a substantially lower risk of intraoperative and periprosthetic fractures
Demonstration of multi-channel 80 Gbit/s integrated transmitter and receiver for wavelength-division multiplexing passive optical network and fronthauling applications
The performance evaluation of a multi-channel transmitter that employs an arrayed reflective electroabsorption modulator-based photonic integrated circuit and a low-power driver array in conjunction with a multi-channel receiver incorporating a pin photodiode array and integrated arrayed waveguide grating is reported. Due to their small footprint, low power consumption and potential low cost, these devices are attractive solutions for future mobile fronthaul and next generation optical access networks. A BER performance of <10(-9) at 10.3 Gbit/s per channel is achieved over 25 km of standard single mode fibre. The transmitter/receiver combination can achieve an aggregate bit rate of 82.4 Gbit/s when eight channels are active
Measuring airway surface liquid depth in ex vivo mouse airways by X-ray imaging for the assessment of cystic fibrosis airway therapies
In the airways of those with cystic fibrosis (CF), the leading pathophysiological hypothesis is that an ion channel defect results in a relative decrease in airway surface liquid (ASL) volume, producing thick and sticky mucus that facilitates the establishment and progression of early fatal lung disease. This hypothesis predicts that any successful CF airway treatment for this fundamental channel defect should increase the ASL volume, but up until now there has been no method of measuring this volume that would be compatible with in vivo monitoring. In order to accurately monitor the volume of the ASL, we have developed a new x-ray phase contrast imaging method that utilizes a highly attenuating reference grid. In this study we used this imaging method to examine the effect of a current clinical CF treatment, aerosolized hypertonic saline, on ASL depth in ex vivo normal mouse tracheas, as the first step towards non-invasive in vivo ASL imaging. The ex vivo tracheas were treated with hypertonic saline, isotonic saline or no treatment using a nebuliser integrated within a small animal ventilator circuit. Those tracheas exposed to hypertonic saline showed a transient increase in the ASL depth, which continued for nine minutes post-treatment, before returning to baseline by twelve minutes. These findings are consistent with existing measurements on epithelial cell cultures, and therefore suggest promise for the future development of in vivo testing of treatments. Our grid-based imaging technique measures the ASL depth with micron resolution, and can directly observe the effect of treatments expected to increase ASL depth, prior to any changes in overall lung health. The ability to non-invasively observe micron changes in the airway surface, particularly if achieved in an in vivo setting, may have potential in pre-clinical research designed to bring new treatments for CF and other airway diseases to clinical trials.Kaye S. Morgan, Martin Donnelley, David M. Paganin, Andreas Fouras, Naoto Yagi, Yoshio Suzuki, Akihisa Takeuchi, Kentaro Uesugi, Richard C. Boucher, David W. Parsons, Karen K. W. Si
The comprehensive cohort model in a pilot trial in orthopaedic trauma
Background: The primary aim of this study was to provide an estimate of effect size for the functional outcome of
operative versus non-operative treatment for patients with an acute rupture of the Achilles tendon using
accelerated rehabilitation for both groups of patients. The secondary aim was to assess the use of a
comprehensive cohort research design (i.e. a parallel patient-preference group alongside a randomised group) in
improving the accuracy of this estimate within an orthopaedic trauma setting.
Methods: Pragmatic randomised controlled trial and comprehensive cohort study within a level 1 trauma centre.
Twenty randomised participants (10 operative and 10 non-operative) and 29 preference participants (3 operative
and 26 non-operative). The ge range was 22-72 years and 37 of the 52 patients were men. All participants had an
acute rupture of their Achilles tendon and no other injuries. All of the patients in the operative group had a simple
end-to-end repair of the tendon with no augmentation. Both groups then followed the same eight-week
immediate weight-bearing rehabilitation programme using an off-the-shelf orthotic. The disability rating index (DRI;
primary outcome), EQ-5D, Achilles Total Rupture Score and complications were assessed ed at two weeks, six
weeks, three months, six months and nine months after initial injury.
Results: At nine months, there was no significant difference in DRI between patients randomised to operative or
non-operative management. There was no difference in DRI between the randomised group and the parallel
patient preference group. The use of a comprehensive cohort of patients did not provide useful additional
information as to the treatment effect size because the majority of patients chose non-operative management.
Conclusions: Recruitment to clinical trials that compare operative and non-operative interventions is notoriously
difficult; especially within the trauma setting. Including a parallel patient preference group to create a
comprehensive cohort of patients has been suggested as a way of increasing the power of such trials. In our
study, the comprehensive cohort model doubled the number of patients involved in the study. However, a strong
preference for non-operative treatment meant that the increased number of patients did not significantly increase
the ability of the trial to detect a difference between the two interventions
The quest for companions to post-common envelope binaries: I. Searching a sample of stars from the CSS and SDSS
As part of an ongoing collaboration between student groups at high schools
and professional astronomers, we have searched for the presence of
circum-binary planets in a bona-fide unbiased sample of twelve post-common
envelope binaries (PCEBs) from the Catalina Sky Survey (CSS) and the Sloan
Digital Sky Survey (SDSS). Although the present ephemerides are significantly
more accurate than previous ones, we find no clear evidence for orbital period
variations between 2005 and 2011 or during the 2011 observing season. The
sparse long-term coverage still permits O-C variations with a period of years
and an amplitude of tens of seconds, as found in other systems. Our
observations provide the basis for future inferences about the frequency with
which planet-sized or brown-dwarf companions have either formed in these
evolved systems or survived the common envelope (CE) phase.Comment: accepted by A&
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