1737 Slices
Medium 9781780644370

8 Mechanism of Cry1Ac Resistance in Cabbage Loopers – A Resistance Mechanism Selected in Insect Populations in an Agricultural Environment

Soberon, M.; Gao, Y.; Bravo, A. CABI PDF

8

Mechanism of Cry1Ac Resistance in Cabbage Loopers –

A Resistance Mechanism Selected in Insect Populations in an

Agricultural Environment

Ping Wang*

Department of Entomology, Cornell University, New York State

Agricultural Experiment Station, Geneva, New York, USA

Summary

The development of resistance to Bacillus thuringiensis (Bt) in insect populations in agriculture not only depends on the level of resistance conferred by a selected resistance mechanism, but also on the fitness cost associated with the resistance mechanism under specific ecological and environmental conditions. Bt resistance in the cabbage looper (Trichoplusia ni), which was identified by Janmaat and Myers (2003), is a case of

Bt resistance evolved in an agricultural system, and is used in this chapter to review and discuss the mechanism of Cry1Ac resistance that is selected in an agricultural environment.

8.1 Introduction

Resistance of insects to pesticide sprays in agriculture has been observed for a century

(Melander, 1914). Under selection pressure by pesticide applications, thousands of cases of pesticide resistance in hundreds of arthropod species have been recorded (MotaSánchez et al., 2008). Since the first report of insect resistance to Bacillus thuringiensis (Bt) in 1985 (McGaughey, 1985), the potential

See All Chapters
Medium 9789381159613

Chapter 6

Krishan Kant Sharma Laxmi Publications PDF

Surface Topography

115

the substrate material may be deformed plastically, which increases the number of dislocations reaching the surface. Dislocations form strong catalytic sites for chemical reactions and this effect is known as ‘mechanical activation’. An intense plastic deformation at a worn surface is quite common during wear and friction and the consequent mechanical activation can exert a strong influence on the formation of a lubricating film.

y

m

4

A σ E (2.3β)

3

y

Ar = hpA (2.3b)2

0.5

\ r =

\ w =

6.2

(2.3β)

0

( z − d)

y

m

0

(z, C) dc dz

NC

f

2

0

m

(z − d )

1.5

y

0

m

f (z, C) dc dz

N C

Surface Topography

Surface topography is the study of the surface lay where roughness height and waviness components of surface imperfections at an atomic level are matched by macroscopic deviations from flatness. apart from the cleaved faces of mica , are rough. Roughness means that most parts of a surface are not flat but form either a peak or a valley. amplitude between the peaks and valleys for engineering surfaces is about one micrometre. The profile of a rough surface is almost random unless some regular features have been deliberately introduced.

See All Chapters
Medium 9781780648422

PART III: GENDER AND RURAL IDENTITY

Bock, B.B.; Shortall, S. CABI PDF

12 

Rurality and Gender Identity

S. Shortall*

Newcastle University, Newcastle upon Tyne, UK

Introduction

When Bettina Bock wrote the introduction to the identity section of Rural Gender Rela­ tions in 2006, she noted that it was in the second half of the 1990s that researchers in

Western countries really began to look at the construction of gender identities in the rural setting. This is an area that has developed significantly since then. It concentrated initially on the identity of farm women and men. Studies then broadened in scope to consider how the rural might intersect with other factors and shape gender.

She also noted that the focus on identity was a predominantly Western one and it was of less interest in the developing world.

Ten years on, this remains the case. She commented that with modernization and globalization the economic position and social status of traditional rural professions weaken. More and more farmers, fishers and foresters have difficulties remaining as the primary breadwinner. Marshall (2001), Ni

See All Chapters
Medium 9789351382492

CH1-2

Saradindu Panda Laxmi Publications PDF

INTRODUCTION

TO

ASIC

11

Fig. 1.12

1.9 LOOK-UP TABLES

The way logic functions are implemented in a FPGA is another key feature.

Logic blocks that carry out logical functions are look-up tables (LUTs), implemented as memory, or multiplexer and memory.

Figure 1.13 shows these aternatives, together with an example of memory contents for some basic operations.

A 2n – 1 ROM can implement any n-bit function. Typical sizes for n are 2, 3, 4 or 5.

In Fig. 1.13 (a), an n-bit LUT is implemented as a 2n – 1 memory; the input address selects one of 2n memory locations. The memory locations (latches) are normally loaded with values from user’s configuration bit-stream.

In Fig. 1.13 (b), the multiplexer control inputs are the LUT inputs. The result is a generalpurpose “logic gate.” An n-LUT can implement any n-bit function. An n-LUT is a direct implementation of a function truth table.

Each latch location holds the value of the function corresponding to one input combination.

(a)

(b)

(c)

Fig. 1.13. Look-up table implemented as (a) memory or (b) multiplexer and memory

See All Chapters
Medium 9781601323286

Females in Software Engineering Teams: A Social Sensitivity Perspective

Hamid R. Arabnia, Leonidas Deligiannidis, George Jandieri, Ashu M. G. Solo, Fernando G. Tinetti CSREA Press PDF

Int'l Conf. Software Eng. Research and Practice | SERP'14 |

77

Females in Software Engineering Teams: A Social

Sensitivity Perspective

Sourabh Khosla1, Lisa L. Bender2, Gursimran S. Walia3, Kendall Nygard4

North Dakota State University134, University of Houston – Clear Lake2

Department of Computer Science

Fargo, ND 58108134; Houston, Texas, USA2

{sourabh.khosla1, gursimran.walia3, Kendall.Nygard4} @ ndsu.edu; bender@uhcl.edu2

Abstract— Software Development is a complex and timedemanding task which requires a group of individuals working effectively as a team for long durations of times. Achieving effectiveness in productivity and quality of work is a challenging task that needs investment and commitment. A recent study conducted at MIT established that teams with greater social sensitivity (SS) tend to perform better when completing a variety of specific collaborative tasks. SS is an empathic ability to correctly understand feelings and perspective of others, and is clearly measureable. However their study was based only on set of generic tasks carried for a short period of time which required only hours to finish. Software development projects require teams to work collaboratively for much longer durations and more complicated tasks. Our goal is to determine if previous research that validated that adding more women to the team improves the team’s social intelligence, which was not focused on students or professionals in scientific or technical fields, is germane for people in computing disciplines. This paper reports the results that investigate the presence of females in the teams, and how the “female factor” effects the average team social sensitivity, team performance activities and the satisfaction achieved during the tenure of team projects.

See All Chapters

See All Slices