Conservation agriculture-based sustainable intensification (CASI) is gaining prominence as an agricultural pathway to poverty reduction and enhancement of sustainable food systems among government and development actors in the Eastern Gangetic Plains (EGP) of South Asia. Despite substantial investment in research and extension programs and a growing understanding of the agronomic, economic and labor-saving benefits of CASI, uptake remains limited. This study explores farmer experiences and perspectives to establish why farmers choose not to implement CASI systems despite a strong body of recent scientific evidence establishing the benefits of them doing so. Through thematic coding of semi-structured interviews, key constraints are identified, which establishes a narrative that current households' resources are insufficient to enable practice change, alongside limited supporting structures for resource supplementation. Such issues create a dependency on subsidies and outside support, a situation that is likely to impact any farming system change given the low-risk profiles of farmers and their limited resource base. This paper hence sets out broad implications for creating change in smallholder farming systems in order to promote the adoption of sustainable agricultural technologies in resource-poor smallholder contexts, especially with regard to breaking the profound poverty cycles that smallholder farmers find themselves in and which are unlikely to be broken by the current set of technologies promoted to them.

Objective: Several studies have provided prevalence estimates of posttraumatic stress disorder (PTSD) related to the September 11, 2001 (9/11) attacks in broadly affected populations, although without sufficiently addressing qualifying exposures required for assessing PTSD and estimating its prevalence. A premise that people throughout the New York City area were exposed to the attacks on the World Trade Center (WTC) towers and are thus at risk for developing PTSD has important implications for both prevalence estimates and service provision. This premise has not, however, been tested with respect to DSM-IV-TR criteria for PTSD. This study examined associations between geographic distance from the 9/11 attacks on the WTC and reported 9/11 trauma exposures, and the role of specific trauma exposures in the development of PTSD.

Methods: Approximately 3 years after the attacks, 379 surviving employees (102 with direct exposures, including 65 in the towers, and 277 with varied exposures) recruited from 8 affected organizations were interviewed using the Diagnostic Interview Schedule/Disaster Supplement and reassessed at 6 years. The estimated closest geographic distance from the WTC towers during the attacks and specific disaster exposures were compared with the development of 9/11–related PTSD as defined by the Diagnostic and Statistical Manual, Fourth Edition, Text Revision.

Results: The direct exposure zone was largely concentrated within a radius of 0.1 mi and completely contained within 0.75 mi of the towers. PTSD symptom criteria at any time after the disaster were met by 35% of people directly exposed to danger, 20% of those exposed only through witnessed experiences, and 35% of those exposed only through a close associate’s direct exposure. Outside these exposure groups, few possible sources of exposure were evident among the few who were symptomatic, most of whom had preexisting psychiatric illness.

Conclusions: Exposures deserve careful consideration among widely affected populations after large terrorist attacks when conducting clinical assessments, estimating the magnitude of population PTSD burdens, and projecting needs for specific mental health interventions.

(Disaster Med Public Health Preparedness. 2011;5:S205-S213)

The motivation to write this paper arose out of the following problem which was posed in a recent mathematical olympiad:

Given a polynomial P(X) with integer coefficients, show that there exist non-zero polynomials Q(X), R(X) with integer coefficients such that P(X)Q(X) is a polynomial in X2 and P(X)R(X) is a polynomial in X3.

For instance, if P(X) = 2 − 5X + 3X2 + 12X3, then we notice that Q (X) = 2 + 5X + 3X2 − 12X3 serves the purpose for the first part, viz.

A moment's thought makes it fairly evident that this trick easily solves the first part of the problem for a general polynomial P(X).

We compute commutativity degrees of wreath products of finite Abelian groups A and B. When B is fixed of order n the asymptotic commutativity degree of such wreath products is 1/n2. This answers a generalized version of a question posed by P. Lescot. As byproducts of our formula we compute the number of conjugacy classes in such wreath products, and obtain an interesting elementary number-theoretic result.

The detection of cervical lymph nodal metastasis and carotid artery invasion by metastatic lymph nodes is an important issue in the management of head and neck malignancies. This study compared the evaluation of metastasis by palpation, ultrasonography (USG) and computed tomography (CT) in patients with known head and neck malignancies.

Twenty-five consecutive patients with head and neck malignancy were prospectively evaluated for the presence of cervical lymphadenopathy and carotid artery invasion. All patients underwent clinical examination (palpation), USG and CT examination. A modified CT criteria was employed which yielded acceptable results for the detection of metastatic nodes. Radical neck dissection was performed for 26 neck sides, and the results of pre-operative evaluation were confirmed by the surgical and histopathological findings.

Palpation, ultrasound and CT have comparable sensitivity in the determination of metastasis involving cervical lymph nodes. Thus palpation should be employed as the primary method of assessment of secondaries in the neck.

However, palpation is less sensitive than CT and USG in the detection of carotid artery involvement, hence the clinical suspicion of arterial invasion should be confirmed by either CT or USG which have similar accuracy in the detection of carotid artery invasion.