1,054 research outputs found
STUDIES ON HIBISCUS CANNABINUS, HIBISCUS SABDARIFFA, AND CANNABINUS SATIVA PULP TO BE A SUBSTITUTE FOR SOFTWOOD PULP- PART 2: SAS-AQ AND NSSC-AQ DELIGNIFICATION PROCESSES
Hibiscus cannabinus, Cannabis sativa, and Hibiscus sabdariffa, fast growing productive annual plants, could provide fiber necessary to partially alleviate the world’s fiber deficit. The present study aimed at producing high yield pulp and the best mechanical strength properties with minimum impact on environment by SAS-AQ, and NSSC-AQ pulping processes. A total alkali of 13% (as Na2O), an alkali ratio of 0.80, and a Na2SO3 charge 11.70% (as Na2O) were found optimum to reduce maximum kappa number. A lower kappa number and good strength properties were achieved by increasing total alkali and Na2SO3 charge. SAS-AQ pulps showed good response towards CEHH bleaching. The NSSC-AQ pulping was conducted at a total alkali charge of 8% (as Na2O) by varying the ratio of sulphite-to-carbonate (100:0-0:100), and cooking time (60-120 min) at 1600C. A ratio of sulphite-to-carbonate 60:40 was suitable for corrugating medium (cooking time 60 min), while a ratio of sulphite-to-carbonate 70:30 showed better strength properties (longer cooking time)
Grand canonical ensemble in generalized thermostatistics
We study the grand-canonical ensemble with a fluctuating number of degrees of
freedom in the context of generalized thermostatistics. Several choices of
grand-canonical entropy functional are considered. The ideal gas is taken as an
example.Comment: 14 pages, no figure
Fission of a multiphase membrane tube
A common mechanism for intracellular transport is the use of controlled
deformations of the membrane to create spherical or tubular buds. While the
basic physical properties of homogeneous membranes are relatively well-known,
the effects of inhomogeneities within membranes are very much an active field
of study. Membrane domains enriched in certain lipids in particular are
attracting much attention, and in this Letter we investigate the effect of such
domains on the shape and fate of membrane tubes. Recent experiments have
demonstrated that forced lipid phase separation can trigger tube fission, and
we demonstrate how this can be understood purely from the difference in elastic
constants between the domains. Moreover, the proposed model predicts timescales
for fission that agree well with experimental findings
GPS-Based Intra-Row Weed Control System: Performance and Labor Savings
Researchers at UC Davis and elsewhere have demonstrated the technical feasibility of using
RTK-GPS technology to automatically create crop plant maps at planting (Sun et al., 2010;
Perez-Ruiz, 2011). This paper describes the development and field evaluation of a
completely automatic system for intra-row weed control in tomato fields. This system uses an
automatically generated GPS crop plant map to automatically control the path of a set of
mechanical intra-row weed knives in order to kill weeds growing between tomato plants in
the seedline. The manual labor savings were evaluated in controlled field trials and the labor
savings benefits associated with the use of this system are reported
Nonequilibrium Probabilistic Dynamics of the Logistic Map at the Edge of Chaos
We consider nonequilibrium probabilistic dynamics in logistic-like maps
, at their chaos threshold: We first introduce many
initial conditions within one among intervals partitioning the phase
space and focus on the unique value for which the entropic form
{\it linearly} increases with
time. We then verify that vanishes like
[]. We finally exhibit a new finite-size
scaling, . This
establishes quantitatively, for the first time, a long pursued relation between
sensitivity to the initial conditions and relaxation, concepts which play
central roles in nonextensive statistical mechanics.Comment: Final version with new Title and small modifications. REVTeX, 8 pages
and 4 eps figure
Comment on "On the importance of the free energy for elasticity under pressure"
Marcus et al. (Marcus P, Ma H and Qiu S L 2002 J. Phys.: Condens. Matter 14
L525) claim that thermodynamic properties of materials under pressure must be
computed using the Gibbs free energy , rather than the internal energy .
Marcus et al. state that ``The minima of , but not of , give the
equilibrium structure; the second derivatives of , but not of , with
respect to strains at the equilibrium structure give the equilibrium elastic
constants.'' Both statements are incorrect.Comment: Commen
Remotely acting SMCHD1 gene regulatory elements: in silico prediction and identification of potential regulatory variants in patients with FSHD
Background: Facioscapulohumeral dystrophy (FSHD) is commonly associated with contraction of the D4Z4 macro-satellite repeat on chromosome 4q35 (FSHD1) or mutations in the SMCHD1 gene (FSHD2). Recent studies have shown that the clinical manifestation of FSHD1 can be modified by mutations in the SMCHD1 gene within a given family. The absence of either D4Z4 contraction or SMCHD1 mutations in a small cohort of patients suggests that the disease could also be due to disruption of gene regulation. In this study, we postulated that mutations responsible for exerting a modifier effect on FSHD might reside within remotely acting regulatory elements that have the potential to interact at a distance with their cognate gene promoter via chromatin looping. To explore this postulate, genome-wide Hi-C data were used to identify genomic fragments displaying the strongest interaction with the SMCHD1 gene. These fragments were then narrowed down to shorter regions using ENCODE and FANTOM data on transcription factor binding sites and epigenetic marks characteristic of promoters, enhancers and silencers
Core and Mini Core Approaches for Enhancing Use of Germplasm in Crop Improvement
Domestication of plants began long ago when the nomadic human beings turned from gatherers
to growers and started growing plants of their choice for food and other needs. Since then man
has depended heavily on biodiversity including plants and it’s parts as source of food. Crop
diversity is part of the biological diversity and includes the resources that contribute to people’s
livelihoods by providing food, feed, medicine, fiber, clothing, shelter and energy. Hence, it
contributes towards achieving the global objectives of food security, poverty alleviation,
environment protection, and sustainable development. Crop diversity is a major component of
crop improvement and is required for both short-term and long-term food security and to
increase productivity and reduce malnutrition..........
Identification of diverse groundnut germplasm: sources of early maturity in a core collection
A groundnut core collection was evaluated in two seasons to identify 21 early maturing landraces. Phenotypic diversity of these 21 early maturing landraces was assessed in three rainy and five post-rainy seasons, along with the three known sources of early maturity (Chico, Gangapuri, and JL 24). The new sources differed in 8 of 14 morphological traits studied. Of the 14 agronomic and 2 quality traits studied, 8 yield and yield-component traits were evaluated at two harvest dates. The landraces matured in 80-90 days after sowing (DAS), similar to Chico and Gangapuri (80-90 DAS) and earlier than JL 24 (90-95 DAS). Four new early maturing landraces [ICG 4558 (India); ICG 4890 (Argentina); ICG 9930 (Zimbabwe); ICG 11605 (Bolivia)], with predominantly three to four seeds per pod, were identified as additional sources for breeding confectionery groundnut varieties. Correlation coefficients between the observations made at the two harvest dates for the seven yield traits were ≥0.71, indicating a single observation is sufficient at 75 DAS or 90 DAS in initial characterization. Correlation between pod yield and 100-seed weight was significant in all the eight seasons individually and overall at 90 DAS. Presence of additional phenotypic diversity in the new early maturity landraces was detected. Principal component analysis (PCA) using the first 10 PC scores delineated the 21 landraces into three clusters. The formation of these clusters could neither be explained on the basis of geographic areas of landraces collection nor on the basis of botanical varieties. This might reflect the nascent variation acquired by the landraces in their secondary habitats, under ecologically similar conditions, independent of their countries of origin. Landraces in clusters 2 and 3 showed a wide range for several agronomic traits, indicating their usefulness in breeding programs for developing early maturing high yielding broad based cultivars
Development of core collection in pigeonpea [Cajanus cajan (L.) Millspaugh] using geographic and qualitative morphological descriptors
Pigeonpea is an important pulse crop grown by smallholder farmers in the semi-arid tropics. Most of the pigeonpea cultivars grown to date are selections from the landraces, with a narrow genetic base. With the expansion of the crop to newer areas, problems of local importance are to be addressed. Hence, an economically feasible and faster germplasm evaluation mechanism, such as a core collection, is required. This article describes the development of core collection from 12,153 pigeonpea accessions collected from 56 countries and maintained at ICRISAT, Patancheru, India. The germplasm accessions from 56 countries were placed under 14 clusters based primarily on geographic origin. Data on 14 qualitative morphological traits were used for cluster formation by Ward’s method. From each cluster ≈10% accessions were randomly selected to constitute a core collection comprising 1290 accessions. Mean comparisons using Newman–Keuls test, variances’ comparisons by Levene’s test, and comparison of frequency distribution by χ2-test indicated that the core collection was similar to that of the entire collection for various traits and the genetic variability available in the entire collection is preserved in the core collection. The Shannon–Weaver diversity index for different traits was also similar for both entire and core collection. All the important phenotypic associations between different traits available in the entire collection were preserved in the core collection. The core collection constituted in the present study facilitates identification of useful traits economically and expeditiously for use in pigeonpea improvemen
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