Climate change at the ecosystem scale: a 50-year record in New Hampshire

Observing the full range of climate change impacts at the local scale is difficult. Predicted rates of change are often small relative to interannual variability, and few locations have sufficiently comprehensive long-term records of environmental variables to enable researchers to observe the fine-scale patterns that may be important to understanding the influence of climate change on biological systems at the taxon, community, and ecosystem levels. We examined a 50-year meteorological and hydrological record from the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, an intensively monitored Long-Term Ecological Research site. Of the examined climate metrics, trends in temperature were the most significant (ranging from 0.7 to 1.3 °C increase over 40–50 year records at 4 temperature stations), while analysis of precipitation and hydrologic data yielded mixed results. Regional records show generally similar trends over the same time period, though longer-term (70–102 year) trends are less dramatic. Taken together, the results from HBEF and the regional records indicate that the climate has warmed detectably over 50 years, with important consequences for hydrological processes. Understanding effects on ecosystems will require a diversity of metrics and concurrent ecological observations at a range of sites, as well as a recognition that ecosystems have existed in a directionally changing climate for decades, and are not necessarily in equilibrium with the current climate

Heap Reference Analysis Using Access Graphs

Despite significant progress in the theory and practice of program analysis, analysing properties of heap data has not reached the same level of maturity as the analysis of static and stack data. The spatial and temporal structure of stack and static data is well understood while that of heap data seems arbitrary and is unbounded. We devise bounded representations which summarize properties of the heap data. This summarization is based on the structure of the program which manipulates the heap. The resulting summary representations are certain kinds of graphs called access graphs. The boundedness of these representations and the monotonicity of the operations to manipulate them make it possible to compute them through data flow analysis. An important application which benefits from heap reference analysis is garbage collection, where currently liveness is conservatively approximated by reachability from program variables. As a consequence, current garbage collectors leave a lot of garbage uncollected, a fact which has been confirmed by several empirical studies. We propose the first ever end-to-end static analysis to distinguish live objects from reachable objects. We use this information to make dead objects unreachable by modifying the program. This application is interesting because it requires discovering data flow information representing complex semantics. In particular, we discover four properties of heap data: liveness, aliasing, availability, and anticipability. Together, they cover all combinations of directions of analysis (i.e. forward and backward) and confluence of information (i.e. union and intersection). Our analysis can also be used for plugging memory leaks in C/C++ languages.Comment: Accepted for printing by ACM TOPLAS. This version incorporates referees' comment

Étude expérimentale de la formulation de mortier a base de sable silteux du Togo et de liant de sachets plastiques type « voltic »

La présente étude est destinée à valoriser les déchets plastiques par la recherche d’une formule optimale de mortier à base de sable silteux du Togo et de sachets plastiques fondus du type « voltic » offrant des propriétés mécaniques optimales. Trente six (36) échantillons de mortier à base de mélange de sable silteux et de liant de sachets plastiques à des dosages variant de 7% à 28% ont été préparés et soumis aux essais physiques et mécaniques après imbibition ou non dans de l’eau. Il ressort des résultats que le dosage en liant de sachets plastiques offrant de résistance optimale en compression (σc), au fendage (τd), en traction par flexion (σf) et par fendage (σd) varient de 16% à 22% avec des résistances à la rupture respectives d’environ 10,3 MPa (à 22%), 2,2 MPa (à 16%), 5,3 MPa (à 18%) et 1,4 MPa (à 16%). Le matériau présente des modules d’élasticité en compression (Ec), en flexion (Ef) et au fendage (Gd) respectivement d’environ 3 800 MPa, 700 MPa et 60 MPa pour des taux de liants de 22%. Pour de faibles taux de liants (8 à 10%), la densité du mortier et son absorption d’eau (en masse) sont optimales (respectivement de 1,95% et 0,29%). Cette absorption d’eau est nulle pour les teneurs en liant supérieures à 18% montrant le comportement étanche des mortiers. Les mortiers peuvent donc être utilisés pour les travaux de pavages, d’étanchement des toitures et de murs pour des taux de liants compris entre 18 à 22%.Mots-clés : mortier, sachets plastiques, sable silteux, eau, propriétés physico-mécaniques

Study of infective morbidity following gynecological surgeries

Background: Post-operative wound infection is a common nosocomial infection all over the world. It is responsible for increase in physical and psychological stress to the patient. It also increases the cost of treatment due to prolonged hospitalization. Present study was carried to find out the post-operative wound infection, morbidity and the risk factors.Methods: Prospective cross sectional study was carried out at tertiary care teaching hospital for a period of six months. Consecutive 57 cases of surgical site infections (SSI) following obstetric and gynecological abdominal surgery were analyzed.Results: It was observed that the incidence of SSI was 2.8 percent. Overweight, previous laparotomy scars, emergency surgery and prolong labour were the common risk factors associated with the development of SSI. Certain epidemiological and environmental factors like under nutrition, rural  area residence, poverty, illiteracy, ignorance, poor general hygiene, Surgical site infections(SSI) were more commonly observed following emergency operations; laparotomies performed for large ovarian tumours, malignancies and ruptured ectopic pregnancies. Caesarean sections performed for prolong labour, prolong premature rupture membranes, prolonged second stage had more likelihood of development of sepsis. Occurrence of SSI resulted in significant prolongation of hospital stay.Conclusions: The incidence of SSI in the present study was within acceptable limits. Regular surveillance for SSI in the hospital and sensitization of staff regarding consequences of SSI would go a long way in further reduction in the rate of SSI

Towards a method for rigorous development of generic requirements patterns

We present work in progress on a method for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. Our chosen application domain is the failure detection and management function for engine control systems: here generic requirements drive a software product line of target systems. A pilot formal specification and design exercise is undertaken on a small (twosensor) system element. This exercise has a number of aims: to support the domain analysis, to gain a view of appropriate design abstractions, for a B novice to gain experience in the B method and tools, and to evaluate the usability and utility of that method.We also present a prototype method for the production and verification of a generic requirement set in our UML-based formal notation, UML-B, and tooling developed in support. The formal verification both of the structural generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

Comparative study of peri-operative outcome following laparotomy versus laparoscopic technique of abdominal hysterectomy for benign gynaecological lesions

Background: Laparoscopic technique of hysterectomy is becoming increasingly popular in developing and developed world. Laparoscopic hysterectomy is a minimal access procedure that allows patients to recover faster. The study was undertaken to assess the impact of two abdominal techniques (laparoscopic and conventional laparotomy) on various variables like operative time, hospital stay, complications and convalescence period.Methods: An observational longitudinal study was carried out at tertiary care centre. Two hundred and ten women, as per inclusion and exclusion criteria, who had undergone abdominal hysterectomy for benign uterine pathology, either by laparotomy (Group A) or by laparoscopic technique (Group B) during study period were included. Data was analyzed and compared by using different variables between two methods of hysterectomy, using percentages and Chi square test for normal distribution. P value less than 0.05 was considered significant.Results: The mean duration of surgery was 100 minutes in group A and 175 minutes in Group B. There were two cases (1.90%) of minor injury to urinary bladder in Group A and one case (0.95%) of thermal injury to urinary bladder in Group B. The mean blood loss was around 240 ml and 70 ml in Group A and B respectively. The need for postoperative analgesia was observed in 100% cases from Group A and 38.09% from group B. The average duration required for out of bed ambulation was 25 hours and 14 hours in Group A and B respectively. The mean hospital stay in group A and B was 7.5 days and 3.5 days respectively.Conclusions: Following laparoscopic hysterectomy, women had less morbidity, less need for post-operative pain relief, had early ambulation, short hospital stay and early resumption of routine activities at home as compared to women who had undergone abdominal hysterectomy by conventional method

Diverse NLR immune receptors activate defence via the RPW8-NLR NRG1

Most land plant genomes carry genes that encode RPW8-NLR Resistance (R) proteins. Angiosperms carry two RPW8-NLR subclasses: ADR1 and NRG1. ADR1s act as 'helper' NLRs for multiple TIR- and CC-NLR R proteins in Arabidopsis. In angiosperm families, NRG1 co-occurs with TIR-NLR Resistance (R) genes. We tested whether NRG1 is required for signalling of multiple TIR-NLRs. Using CRISPR mutagenesis, we obtained an nrg1a-nrg1b double mutant in two Arabidopsis accessions, and an nrg1 mutant in Nicotiana benthamiana. These mutants are compromised in signalling of all TIR-NLRs tested, including WRR4A, WRR4B, RPP1, RPP2, RPP4 and the pairs RRS1/RPS4, RRS1B/RPS4B, CHS1/SOC3 and CHS3/CSA1. In Arabidopsis, NRG1 is required for the hypersensitive cell death response (HR) and full oomycete resistance, but not for salicylic acid induction or bacterial resistance. By contrast, nrg1 loss of function does not compromise the CC-NLR R proteins RPS5 and MLA. RPM1 and RPS2 (CC-NLRs) function is slightly compromised in an nrg1 mutant. Thus, NRG1 is required for full TIR-NLR function and contributes to the signalling of some CC-NLRs. Some NRG1-dependent R proteins also signal partially via the NRG1 sister clade, ADR1. We propose that some NLRs signal via NRG1 only, some via ADR1 only and some via both or neither

Profiles of Disruptive Behavior Across Early Childhood: Contributions of Frustration Reactivity, Physiological Regulation, and Maternal Behavior

Disruptive behavior, including aggression, defiance, and temper tantrums, typically peaks in early toddlerhood and decreases by school entry; however, some children do not show this normative decline. The current study examined disruptive behavior in 318 boys and girls at 2, 4, and 5 years of age and frustration reactivity, physiological regulation, and maternal behavior in the laboratory at 2 years of age. A latent profile analysis resulted in 4 longitudinal profiles of disruptive behavior, which were differentiated by interactions between reactivity, regulation, and maternal behavior. A high profile was associated with high reactivity combined with high maternal control or low regulation combined with low maternal control. Results are discussed from a developmental psychopathology perspective

Investigative power of Genomic Informational Field Theory (GIFT) relative to GWAS for genotype-phenotype mapping

Identifying associations between phenotype and genotype is the fundamental basis of genetic analyses. Inspired by frequentist probability and the work of R.A. Fisher, genome-wide association studies (GWAS) extract information using averages and variances from genotype-phenotype datasets. Averages and variances are legitimated upon creating distribution density functions obtained through the grouping of data into categories. However, as data from within a given category cannot be differentiated, the investigative power of such methodologies is limited. Genomic Informational Field Theory (GIFT) is a method specifically designed to circumvent this issue. The way GIFT proceeds is opposite to that of GWAS. Whilst GWAS determines the extent to which genes are involved in phenotype formation (bottom-up approach), GIFT determines the degree to which the phenotype can select microstates (genes) for its subsistence (top-down approach). Doing so requires dealing with new genetic concepts, a.k.a. genetic paths, upon which significance levels for genotype-phenotype associations can be determined. By using different datasets obtained in ovis aries related to bone growth (Dataset-1) and to a series of linked metabolic and epigenetic pathways (Dataset-2), we demonstrate that removing the informational barrier linked to categories enhances the investigative and discriminative powers of GIFT, namely that GIFT extracts more information than GWAS. We conclude by suggesting that GIFT is an adequate tool to study how phenotypic plasticity and genetic assimilation are linked.</p