Institutional factors affecting irrigation performance in Pakistan: research and policy priorities

The strong irrigation tradition has sustained the broad based community interest in irrigation. The result is a very complex institutional milieu in which a set of formally established irrigation rules and organizations exists side by side with an intricate set of social institutions. The two sets act like a dual system often in conflict with each other. The authors, while analyzing the present institutional barriers, have highlighted the importance of irrigation rules and procedures in the institutional framework.Irrigation management, Performance evaluation, Institutions, Poverty, Legislation, Food Security and Poverty, Institutional and Behavioral Economics,

ALPHA-CAPTURE REACTION RATES FOR 22NE(α,N)25MG AND 22NE(α,γ) 26MG REACTIONS VIA SUB-COULOMB ALPHA-TRANSFER AND THEIR EFFECTS ON FINAL ABUNDANCES OF S-PROCESS ISOTOPES

The ^22Ne(α,n) reaction is an important neutron source reaction for the slow neutron capture process (s-process) in asymptotic giant branch stars. Direct measurements are extremely difficult to carry out at Gamow energies due to the extremely small reaction cross section. The large uncertainties introduced when extrapolating direct measurements at high energies down to the Gamow energies can be overcome by determining the partial α-width of the relevant states using indirect measurements. This can be done using α-transfer reactions at sub-Coulomb energies to reduce the dependence on optical model parameters. The α-transfer reaction of ^22Ne(^^6Li,d)^26Mg was carried out at the Cyclotron Institute at Texas A&M University to study this reaction. It appears that the partial α widths of the near α-threshold resonances of ^26Mg are different from what was previously assumed. This discrepancy affects the final ^22Ne(α,n) reaction rate and the final abundances of the s-process isotopes

ALPHA-CAPTURE REACTION RATES FOR 22NE(α,N)25MG AND 22NE(α,γ) 26MG REACTIONS VIA SUB-COULOMB ALPHA-TRANSFER AND THEIR EFFECTS ON FINAL ABUNDANCES OF S-PROCESS ISOTOPES

The ^22Ne(α,n) reaction is an important neutron source reaction for the slow neutron capture process (s-process) in asymptotic giant branch stars. Direct measurements are extremely difficult to carry out at Gamow energies due to the extremely small reaction cross section. The large uncertainties introduced when extrapolating direct measurements at high energies down to the Gamow energies can be overcome by determining the partial α-width of the relevant states using indirect measurements. This can be done using α-transfer reactions at sub-Coulomb energies to reduce the dependence on optical model parameters. The α-transfer reaction of ^22Ne(^^6Li,d)^26Mg was carried out at the Cyclotron Institute at Texas A&M University to study this reaction. It appears that the partial α widths of the near α-threshold resonances of ^26Mg are different from what was previously assumed. This discrepancy affects the final ^22Ne(α,n) reaction rate and the final abundances of the s-process isotopes

The role of cyanobacterial toxins as grazing inhibitors in the fresh water cladoceran Daphnia magna straus

Life history parameters of the cladoceran Duphnia magna were compared under several combinations of defined media and green alga! diets in order to select a standardized and therefore repeatable culture system for D. magna. It was found that none of the defined media tested were nutritionally sufficient to replace natural media. However, Elendt M4 medium when used in conjunction with Chlorella minutissima was deemed the best combination representing a defined medium for Daphnia culture. It was noted that bacterial contaminants in algal diets can compensate for some of the nutritional deficiencies present in defined culture media. The effects of short term (24 h) and long term (4 - 5 d) exposure to toxic Microcystis aeruginosa on the feeding rate of D. magna were investigated by comparing 24 h feeding rates on Chlorella vulgaris, non-toxic M. aeruginosa (strain CYA 43) and toxic M. aeruginosa (strain PCC 7820). Toxic M. aeruginosa suppressed the feeding rate of D. magna not only on M. aeruginosa itself but afso on other algae present. However the cyanobacterial toxin, microcystin-LR, was not the main causative factor for the feeding inhibition. It was hypothesised that factors present on the surface of M. aeruginosa cells caused a rapid suppression of feeding rate. Inhibition of feeding was further suppressed by the poor quality of M. aeruginosa as a food source for D. magna. Microcystin-LR was the primary cause of the death of daphnids which were exposed to toxic M. aeruginosa cells, confirming that microcystin-LR is toxic to D. magna. However, at concentrations which occur in natural waters, dissolved purified microcystin-LR had no measurable effect on the feeding rate or life history of D. magna. The toxicity of intact cells of M. aeruginosa was three orders of magnitude greater than that of purified microcystin-LR. A difference in bioavailability of microcystin-LR or a cumulative effect of an undescribed toxicant were thought to be the reason for toxicity differences

A review of dental informatics : current trends and future directions

Dental informatics is a rapidly evolving field that combines dentistry with information technology to improve oral health care delivery, research, and education. Electronic health records (EHRs), telehealth, digital imaging, and other digital tools have revolutionised how dental professionals diagnose, treat, and manage oral health conditions. In this review article, we will explore dental informatics's current trends and future directions, focusing on its impact on clinical practice, research, and education. We will also discuss the challenges and opportunities associated with implementing dental informatics and highlight fundamental research studies and innovations in the field

Graphene as Infrared Light Sensor Material

The infrared (IR) photoresponse of graphene synthesized by an atmospheric chemical vapor deposition (CVD) system using a mixture of hydrogen and methane gases was studied. The IR sensor devices were fabricated using graphene films transferred onto a SiO2 substrate by a lift-off process. The quality of graphene was investigated with Raman spectroscopy and optical microscopy. The photoresponse was recorded under the illumination of IR light of wavelength 850 nm and intensity of around 0.216 mW/cm^2. The effects of temperature and hydrogenation on photoconductivity were also studied. It was found that the transient response and recovery times decreased with the temperature increase. The hydrogenation effect also caused a significant decrease in the photoresponse of the device. Although the net change in the photoresponse for IR light was lower at low illumination intensity levels, the transient responses were observed around 100 times faster than the recently reported CNT-based IR sensors.Comment: 8 pages, 8 pictures, and 1 table