Distance from a fishing community explains fish abundance in a no-take zone with weak compliance

There are numerous examples of no-take marine reserves effectively conserving fish stocks within their boundaries. However, no-take reserves can be rendered ineffective and turned into ‘paper parks’ through poor compliance and weak enforcement of reserve regulations. Long-term monitoring is thus essential to assess the effectiveness of marine reserves in meeting conservation and management objectives. This study documents the present state of the 15-year old no-take zone (NTZ) of South El Ghargana within the Nabq Managed Resource Protected Area, South Sinai, Egyptian Red Sea. Previous studies credited willing compliance by the local fishing community for the increased abundances of targeted fish within the designated NTZ boundaries compared to adjacent fished or take-zones. We compared benthic habitat and fish abundance within the NTZ and the adjacent take sites open to fishing, but found no significant effect of the reserve. Instead, the strongest evidence was for a simple negative relationship between fishing pressure and distance from the closest fishing village. The abundance of targeted piscivorous fish increased significantly with increasing distance from the village, while herbivorous fish showed the opposite trend. This gradient was supported by a corresponding negative correlation between the amount of discarded fishing gear observed on the reef and increasing distance from the village. Discarded fishing gear within the NTZ suggested decreased compliance with the no-take regulations. Our findings indicate that due to non-compliance the no-take reserve is no longer functioning effectively, despite its apparent initial successes and instead a gradient of fishing pressure exists with distance from the nearest fishing community

Experimental investigation of a coaxial gyrotron oscillator

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1999.Includes bibliographical references (leaves 157-165).This thesis presents experimental results of a megawatt power level, 140 GHz coaxial gyrotron oscillator. The coaxial gyrotron has the potential to transport very high power electron beams and thus achieve higher microwave output power levels than conventional gyrotrons. A TE2 ,3 coaxial gyrotron was designed to operate at 95 kV, 76 A. This tube was tested to high power with the first high power Inverted Magnetron Injection Gun (IMIG). The IMIG electron gun was tested to 10 MW (105 kV, 93 A), which is the highest power level for a non-relativistic gyrotron gun. Operation of the coaxial gyrotron oscillator yielded power levels of greater than 1 MW in two different configurations: with the coaxial conductor (at 92kV, 70 A, and 16% efficiency) and without the coaxial conductor (85 kV,65 A, and 18% efficiency). We also successfully operated this tube in three configurations (empty cavity, radial output, and axial output) with no beam interception. We observed regimes of dominant single mode and multi-mode operation. We also identified electron beam asymmetries and tube alignment as two major issues, which can limit the performance of a coaxial gyrotron. An unexpected source of magnetic field error was found in the magnetization of the stainless steel parts. All these results have led to techniques for improving not only coaxial gyrotrons but also other gyrotron tubes.(cont.) We also investigated a ferroelectric cathode, which has the potential to achieve higher currents than thermionic cathodes in a simpler, low cost gun. We report the first results on a ferroelectric cathode gun in a magnetron injection gun configuration suitable for use in a gyrotron. It had an annular emitter shape with a diameter of 11.4 cm and a width of 0.25 cm and operated at currents of up to 10 A (1.1 A/cm2) at 8 kV, in 5 Vs flat-top pulses. This result (along with the kiloampere beam obtained at Integrated Applied Physics) demonstrate the scalability of ferroelectric cathodes to large diameter electron beams. Also, the first ever microwaves from a ferroelectric cathode were generated in a collaboration experiment at Tel Aviv University. Finally, we developed a theory to explain the emission process from ferroelectric cathodes. The experiments reported have shown the suitability of ferroelectric cathodes for future microwave generation experiments.by Rahul N. Advani.Ph.D

Takeoff temperatures in Melitaea cinxia butterflies from latitudinal and elevational range limits: a potential adaptation to solar irradiance

International audience1. This study provides evidence that a heliophilic butterfly, the Glanville fritillary (Melitaea cinxia) has adapted differently to environmental variation across latitudes and elevations.2. In cool air, basking M. cinxia orient themselves perpendicular to the sun's rays to gain heat and take off. During flight, solar heating is reduced because orientation perpendicular to the sun is no longer possible and convective cooling occurs. Consequently, M. cinxia have been shown to suffer net heat loss in flight, even in full sunshine. When flight duration is restricted in this way, the takeoff temperature becomes an important thermal adaptation.3. Using a thermal imaging camera, takeoff temperatures were measured in experimental butterflies. Butterflies from the northern range limit in Finland took flight at slightly hotter temperatures than butterflies from the southern limit in Spain, and much hotter than butterflies from the elevational limit (1900–2300 m) in the French Alps. Butterflies from low‐elevation populations in southern France also took off much hotter than did the nearby Alpine population.4. These results suggest that the influence of elevation is different from that of latitude in more respects than ambient temperature. Values of solar irradiance in the butterflies' flight season in each region show that insects from the coolest habitats, Finland and the Alps, experienced similar solar irradiance during basking, but that Finns experienced much lower irradiance in flight. This difference may have favored Finnish butterflies evolving higher takeoff temperatures than Alpine butterflies that also flew in cool air but benefited from more intense radiant energy after takeoff

Anti-tubulin drugs conjugated to anti-ErbB antibodies selectively radiosensitize.

Tumour resistance to radiotherapy remains a barrier to improving cancer patient outcomes. To overcome radioresistance, certain drugs have been found to sensitize cells to ionizing radiation (IR). In theory, more potent radiosensitizing drugs should increase tumour kill and improve patient outcomes. In practice, clinical utility of potent radiosensitizing drugs is curtailed by off-target side effects. Here we report potent anti-tubulin drugs conjugated to anti-ErbB antibodies selectively radiosensitize to tumours based on surface receptor expression. While two classes of potent anti-tubulins, auristatins and maytansinoids, indiscriminately radiosensitize tumour cells, conjugating these potent anti-tubulins to anti-ErbB antibodies restrict their radiosensitizing capacity. Of translational significance, we report that a clinically used maytansinoid ADC, ado-trastuzumab emtansine (T-DM1), with IR prolongs tumour control in target expressing HER2+ tumours but not target negative tumours. In contrast to ErbB signal inhibition, our findings establish an alternative therapeutic paradigm for ErbB-based radiosensitization using antibodies to restrict radiosensitizer delivery

Speech Communication

Contains reports on five research projects.U. S. Air Force (Electronic Systems Division) under Contract AF 19(628)-3325National Science Foundation (Grant GP-Z495)National Institutes of Health (Grant MH-04737-04)National Institutes of Health (Grant NB-0433Z-02)National Aeronautics and Space Administration (Grant NsG-496

Multiomic analysis of oral keratinocytes chronically exposed to shisha

Background: Tobacco is smoked in different form including cigarettes and water pipes. One popular form of water pipe smoking especially in Middle Eastern countries is shisha smoking. Shisha has been associated with various diseases including oral cancer. However, genomic alterations and gene expression changes associated with chronic shisha exposure have not been previously investigated. Objectives: Whole‐exome sequencing and gene expression profiling of immortalized human oral keratinocytes (OKF6/TERT1) cells chronically treated with 0.5% shisha extract for a period of 8 months was undertaken to characterize molecular alterations associated with shisha exposure. Methods: Genomic DNA and RNA were extracted and preprocessed as per manufacturer's instruction and subjected to whole‐exome and transcriptome sequencing using Illumina HiSeq2500 platform. Exome was analyzed using GATK pipeline whereas RNA‐Seq data was analyzed using HiSat2 and HTSeq along with DESeq to elucidate differentially expressed genes. Results: Whole‐exome sequence analysis led to identification of 521 somatic missense variants corresponding to 389 genes RNA‐Seq data revealed 247 differentially expressed genes (≥2‐fold, P‐value<0.01) in shisha treated cells compared to parental cells. Pathway analysis of differentially expressed genes revealed that interferon‐signaling pathway was significantly affected. We predict activation of MAPK1 pathway which is known to play a key role in oral cancer. We also observed allele specific expression of mutant LIMA1 based on RNA‐Seq dataset. Conclusion: Our findings provide insights into genomic alterations and gene expression pattern associated with oral keratinocytes chronically exposed to shisha

The Need for Increased Fidelity in Flight Training Devices to address the ‘Rotorcraft Loss of Control Inflight’ problem

This paper examines the trends in rotorcraft accident statistics, particularly regarding Loss of Control In-flight accidents (LOC-I), with the aim of stimulating interest in new research relevant to this area. Despite recent safety initiatives, LOC-I rotorcraft accidents have been identified as a significant and growing contribution to accident rates. The fixed-wing commercial airline community faced a similar situation starting in the late 1990s and, through a coordinated international effort, developed a new training program to help reduce accident rates. Lessons learned from the fixed-wing work are presented to highlight the need for improved rotorcraft modeling tools to reduce rotorcraft accidents through higher-quality, simulator-based training programs. The findings from previous and ongoing rotorcraft modeling and simulation research are presented, and areas for further research are identified. A proposal is made in the paper for a workshop to bring together the key rotorcraft stakeholders to develop future steps in tackling rotorcraft LOC-I accidents