Asymptotic Charges Cannot Be Measured in Finite Time

To study quantum gravity in asymptotically flat spacetimes, one would like to understand the algebra of observables at null infinity. Here we show that the Bondi mass cannot be observed in finite retarded time, and so is not contained in the algebra on any finite portion of ${\mathscr{I}}^+$. This follows immediately from recently discovered asymptotic entropy bounds. We verify this explicitly, and we find that attempts to measure a conserved charge at arbitrarily large radius in fixed retarded time are thwarted by quantum fluctuations. We comment on the implications of our results to flat space holography and the BMS charges at ${\mathscr{I}}^+$.Comment: 9 pages, 3 figures. v2 typos fixed and minor addition

Occurrence of Vibrio parahaemolyticus in marine prawns and environments

Qualitative studies on the microflora of slime and guts of prawns and of sea water off Nagapattinam showed the presence of Vibrio in the slime and sea water. They were further tested for Vibrio parahaemolyticus types and related bio-types. Evidence of its occurrence is given. This points to the need for further studies on the distribution of this organism in terms of public health significance

Capturing the Benefits of Worker Specialization: Effectsof Managerial and Organizational Task Experience

Learning by doing is a fundamental driver of productivity among knowledge workers. As workers accumulate experience working on certain types of tasks (i.e., they become specialized), they also develop proficiency in executing these tasks. However, previous research suggests that organizations may struggle to leverage the knowledge workers accrue through specialization because specialized workers tend to lose interest and reduce effort during task execution. This study investigates how organizations can improve specialized workers’ performance by mitigating the dysfunctional effects of specialization. In particular, we study how other sources of task experiences from the worker’s immediate manager as well as the organization itself help manage the relationship between worker specialization and performance. We do so by analyzing a proprietary dataset that comprises of 39,162 software service tasks that 310 employees in a Fortune 100 organization executed under the supervision of 92 managers. Results suggest that the manager role experience (i.e., the manager’s experience supervising workers) is instrumental in mitigating the potential negative effect of worker specialization on performance, measured as task execution time. Such influence, however, is contingent on cases in which organizational task experience (i.e., the organization’s experience in executing tasks of the same substantive content as the focal task) is limited. Taken together, our research contributes to multiple streams of research and unearths important insights on how multiple sources of experience beyond the workers themselves can help capture the elusive benefits of worker specialization

Effects of Automated Interventions in Programming Assignments: Evidence from a Field Experiment

A typical problem in MOOCs is the missing opportunity for course conductors to individually support students in overcoming their problems and misconceptions. This paper presents the results of automatically intervening on struggling students during programming exercises and offering peer feedback and tailored bonus exercises. To improve learning success, we do not want to abolish instructionally desired trial and error but reduce extensive struggle and demotivation. Therefore, we developed adaptive automatic just-in-time interventions to encourage students to ask for help if they require considerably more than average working time to solve an exercise. Additionally, we offered students bonus exercises tailored for their individual weaknesses. The approach was evaluated within a live course with over 5,000 active students via a survey and metrics gathered alongside. Results show that we can increase the call outs for help by up to 66% and lower the dwelling time until issuing action. Learnings from the experiments can further be used to pinpoint course material to be improved and tailor content to be audience specific.Comment: 10 page

Capturing the Benefits of Worker Specialization: Effects of Managerial and Organizational Task Experience

Learning by doing is a fundamental driver of productivity among knowledge workers. As workers accumulate experience working on certain types of tasks (i.e., they become specialized), they also develop proficiency in executing these tasks. However, previous research suggests that organizations may struggle to leverage the knowledge workers accrue through specialization because specialized workers tend to lose interest and reduce effort during task execution. This study investigates how organizations can improve specialized workers’ performance by mitigating the dysfunctional effects of specialization. In particular, we study how other sources of task experiences from the worker's immediate manager as well as the organization itself help manage the relationship between worker specialization and performance. We do so by analyzing a proprietary dataset that comprises of 39,162 software service tasks that 310 employees in a Fortune 100 organization executed under the supervision of 92 managers. Results suggest that the manager role experience (i.e., the manager's experience supervising workers) is instrumental in mitigating the potential negative effect of worker specialization on performance, measured as task execution time. Such influence, however, is contingent on cases in which organizational task experience (i.e., the organization's experience in executing tasks of the same substantive content as the focal task) is limited. Taken together, our research contributes to multiple streams of research and unearths important insights on how multiple sources of experience beyond the workers themselves can help capture the elusive benefits of worker specialization

Free-standing graphene films embedded in epoxy resin with enhanced thermal properties

The poor thermal conductivity of polymer composites has long been a deterrent to their increased use in high-end aerospace or defence applications. This study describes a new approach for the incorporation of graphene in an epoxy resin, through the addition of graphene as free-standing film in the polymeric matrix. The electrical and thermal conductivity of composites embedding two different free-standing graphene films was compared to composites with embedded carbon nanotube buckypapers (CNT-BP). Considerably higher thermal conductivity values than those achieved with conventional dispersing methods of graphene or CNTs in epoxy resins were obtained. The characterisation was complemented with a study of the structure at the microscale by cross-sectional scanning electron microscopy (SEM) images and a thermogravimetric analysis (TGA). The films are preconditioned in order to incorporate them into the composites, and the complete manufacturing process proposed allows the production and processing of these materials in large batches. The high thermal conductivity obtained for the composites opens the way for their use in demanding thermal management applications, such as electronic enclosures or platforms facing critical temperature loads.European Defence Agency tender No 17.ESI.OP.066. Study on the Impact of Graphene on Defence Application

A study of patients 'lost' from short course chemotherapy under district tuberculosis programme

A study was undertaken in North Arcot and Raichur districts in South India to find out the reasons for patients getting ‘lost’ from short course chemotherapy. There were 545 (40%) patients ‘lost’ from treatment in North Arcot during 14 months and 219 (46%) in Raichur during 72 months. Approximately half of the ‘lost’ patients from both the districts discontinued treatment within two months from the start of treatment. Due to inadequate or incorrect address, 84 (15%) and 26 (13%) patients could not be traced at North Arcot and Raichur, respectively. Reasons could not be elicited from 39 (7%) and 16 (7%) patients, respectively, as they had migrated. Eighty-two (15%) from North Arcot and 33 (15%) from Raichur had died. For 55 (10%) patients from North Arcot and 15 (7%) from Raichur treatment had been changed. Twenty -three (4%) from North Arcot had actually completed their treatment at a different Peripheral Health Institution. Reasons for stopping treatment were obtained from 262 (48%) and 127 (58%) patients, respectively, from the two districts. Abatement of symptoms (19%, 35%), adverse reactions (22%, 13%), outstation trips (22%, 2%), lack of faith in diagnosis and treatment (10%, 27%) and taking private treatment (9%, 32%) were some of the reasons given by the patients Interviewed respectively from these two districts . Some of the patients gave more than one reason

Surveillance of drug-resistant tuberculosis in the state of Gujarat, India

BACKGROUND: Limited information about the prevalence of drug-resistant tuberculosis (TB) has been reported from India, the country with the world’s highest burden of TB. We conducted a representative state-wide survey in the state of Gujarat (2005 population: 56 million). METHODS: Mycobacterium tuberculosis isolates from a representative sample of new and previously treated smear-positive pulmonary TB (PTB) cases were subjected to drug susceptibility testing (DST) against fi rst-line drugs at a World Health Organization supranational reference laboratory. Isolates found to have at least both isoniazid (INH) and rifampicin (RMP) resistance (i.e., multidrugresistant TB [MDR-TB]) were subjected to second-line DST. RESULTS: Of 1571 isolates from new patients, 1236 (78.7%) were susceptible to all fi rst-line drugs, 173 (11%) had any INH resistance and MDR-TB was found in 37 (2.4%, 95%CI 1.6–3.1). Of 1047 isolates from previously treated patients, 564 (54%) were susceptible to all fi rst-line drugs, 387 (37%) had any INH resistance and MDR-TB was found in 182 (17.4%, 95%CI 15.0–19.7%). Among 216 MDR-TB isolates, 52 (24%) were ofl oxacin (OFX) resistant; seven cases of extensively drug-resistant TB (XDR-TB) were found, all of whom were previously treated cases. CONCLUSION: MDR-TB prevalence remains low among new TB patients in Gujarat, but is more common among previously treated patients. Among MDR-TB isolates, the alarmingly high prevalence of OFX resistance may threaten the success of the expanding efforts to treat and control MDR-TB

Towards cleaner degreasing method in industries: ultrasound-assisted aqueous degreasing process in leather making

Studies on ultrasound-assisted processes are gaining importance due to its effectiveness and facilitating green method in processing. Degreasing of skin/hide prior to tanning process is an important unit operation. Presence of large amounts of natural fat at the interior of skin/hide matrix makes degreasing process a challenging one. Conventionally, organic solvent and/or detergent based degreasing process are employed leading to environmental problems. In the present paper, the use of power ultrasound in aqueous degreasing process has been studied and compared with different degreasing systems. Glutaraldehyde pre-tanning has also been employed for carrying out the degreasing process at ultrasonic bath temperature. The results indicate that there is a significant increase in the degreasing efficiency due to the application of ultrasound. About 2-fold increase in fat removal has been observed due to the use of ultrasound as compared to control under the given process conditions. Comparing the degreasing efficiencies of the solvent with aqueous based ultrasonic processes, about 80% of the solvent degreasing efficiency could be obtained for aqueous degreasing process. This novel ultrasonic process helps in making aqueous degreasing process a viable option, which is eco-friendly even dispensing with temperature control measures