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This article presents a high-efficiency circularly polarized slotted waveguide leaky wave antenna at the W band. A linearly polarized beam-steering antenna is designed by creating an array of longitudinal slots on the WR-10 waveguide and to achieve circular polarization, a single-layer polarization converter has been used. A new technique has been proposed to enhance the overall efficiency of the antenna. The wall thickness of the waveguide containing the radiating slots is reduced to increase the overall radiation efficiency of the provided antenna. The gain of the prototype antenna is above 20 dBi in the intended operating band from 92 GHz to 98 GHz. Furthermore, the antenna provides an average half-power beamwidth (HPBW) of 3.2° in the elevation plane and a cross-polarization below -18 dB in the main beam direction. Attributed to robust structure, reliable fabrication, and simple antenna configuration as well as its superior performance, the proposed structure is a strong candidate for various W band applications.

Reinforcing thermoplastic polymers with natural fibres tends to improve tensile and flexural strength but adversely affect elongation and impact strength. This limits the application of such composites where toughness is a major criterion. In the present work, bamboo fibre reinforced polypropylene (PP) composites were prepared with bamboo fibre content varying from 30% to 50% with improved impact resistance. Homopolymer and copolymer PP were used as the matrix polymer and an elastomer was used (10% by wt.) as an additive in the formulation. Copolymer based composites exhibited superior elongation and impact strength as compared to homopolymer based composites. The adverse impact of elastomer on tensile and flexural strength was more pronounced in homopolymer based composites. The study suggested that the properties of the bamboo composites can be tailored to suit different applications by varying reinforcement and elastomer percentage.

In recent years, there has been a growing interest in injection moulded Fiber Reinforced Polymer (FRP) composites, particularly with the natural fiber reinforcement due to their renewability and eco friendliness. In many of the applications, stiffness and strength are of prime importance in designing of injection moulded engineering parts. Determination of elastic modulus will give the designer flexibility to design the part geometry depending on stiffness requirement for particular application. This paper discusses micromechanical modeling of bamboo short fiber reinforced polypropylene composites. Bamboo polypropylene composites (BPC) were prepared by reinforcing polypropylene homopolymer matrix with short bamboo fibers. Composites with five different reinforcement percentages (10, 20, 30, 40, and 50 wt%) were prepared and tensile test samples were injection moulded. Tensile elastic modulus and strengths of bamboo composites were measured according to ASTM standard. Various micromechanical theoretical models were studied to find best possible model that correlates well with the experimental results. Elastic Modulus predicted by “Halpin-Tsai” model was in close agreement with the experimentally measured values. Strength predicted by “Kelly-Tyson” model also matched very well with the experimental values. Micromechanic-based semi analytical model “Mori–Tanaka” in Digimat-MF (mean-field homogenization) and numerical finite-element modeling (FEM) of BPC using the concept of representative volume element (RVE) have also been studied and results are compared with experimentally measured values.

This comparative study focused on understanding the effect of coupling agent and particle size on weathering behaviour of wood polypropylene composite. Two coupling agents, namely maleic anhydride grafted polypropylene and m-TMI (m-Isopropenyl-α,α? dimethylbenzyl isocyanate) grafted polypropylene were used in preparation of the composites. The composites were exposed to outdoor conditions for one year and changes in surface colour and mechanical properties were measured after 2, 4, 8 and 12 months of natural weathering. During the initial four months of weathering considerable colour change was observed with increase in lightness. Mechanical properties were unaffected largely for the initial four months and thereafter started declining. Overall, tensile strength decreased by about 15 % and flexural strength decreased by about 8 % after one year of weathering. The flexural modulus also decreased by about 10 %. Wood particle size was found to affect the aesthetic and strength of the composites after natural weathering. Coupling agents had a positive impact on mechanical properties however their influence on weathering degradation was not noticeable.

Wood plastic composites (WPCs) are being used for many outdoor applications such as fencing, railing and decking. In outdoor conditions, composites are exposed to varying atmospheric conditions which may influence its mechanical properties. Among the various effects, most predominant one is the moisture absorption due to rainfall. It is necessary to evaluate the effect of moisture absorption/desorption on mechanical properties of WPC. In the present investigation, Melia dubia wood fibre-reinforced polypropylene composites were prepared with and without coupling agent at 40 and 60% fibre loading. Composites were also prepared with three different wood fibre sizes. The composites were exposed to 25 cycles of wetting and drying. During each cycle, the samples were immersed in water for a period of 100 h followed by drying in atmospheric condition for 100 h. Samples were weighed after wetting and drying in each cycle, and mechanical properties were evaluated at 0, 5, 10 and 25 cycles. The results indicated that the composites with higher wood content and fine particle size exhibited higher water absorption and increased loss in mechanical properties. Composites prepared with coupling agent exhibited relative lower moisture absorption and smaller loss in mechanical properties compared to uncoupled composites.

Phenotyping large populations for assessing the variability for wood traits is the basic and critical step for developing improved genotypes/clones in the conventional or molecular marker-based tree improvement programmes of timber-yielding species. Melia dubia is rapidly emerging as a potential timber species with large-scale plantations being raised in different parts of India. In this study, large number of M. dubia trees (n = 940) were phenotyped for girth at breast height, wood basic density and stiffness from six plantations at three different locations, i.e. Yeshwanthpura (Kolar district), Hunsur and adjoining areas (Mysore district) and Kollegal (Mandya district) of Karnataka. Non-destructive tools namely pilodyn penetrometer and stress wave timers were used for phenotyping of wood density and wood stiffness, respectively. Across the locations, pilodyn penetration ranged from 12 to 30 mm and stress wave velocity ranged from 3.45 to 4.54 km/s. Plantations in the Hunsur area were characterized with relatively high pilodyn penetration (means low basic density), whereas stress wave velocity was uniformly distributed in all three locations. 11.68% of total number of trees (3.11% with GBH ≥ 37.5 cm from Yeshwanthpura and 8.57% trees from Kollegal) exhibiting pilodyn penetration range from 12 to 17 mm can be considered for selection for high density and 19.3% of trees (3.9% of trees from Yeshwanthpura, 4.4% trees from Hunsur and 11.02% trees from Kollegal) having stress wave velocity ranging from 4.05 to 4.46 km/s can be considered for high stiffness in the future tree improvement programmes. More than twofolds variation in pilodyn penetration and sufficiently large variation in stress wave velocity provide the opportunity for the development of trait-specific markers.

Plasmodium falciparum leads to a virulent form of malaria. Progress has been achieved in understanding the mechanisms involved in the malarial infection, still there is no effective vaccine to prevent severe infection. An effective vaccine against malaria should be one which can induce immune responses against multiple epitopes in the context of predominantly occurring HLA alleles. In this study, an integrated approach was employed to identify promiscuous peptides of a well-defined sequence of erythrocyte binding antigen-175 and promiscuous peptides for HLA alleles were designed using bioinformatics tools. A peptide with 15 amino acids (ILAIAIYESRILKRK) was selected based on its high binding affinity score and synthesized. This promiscuous peptide was used as stimulating antigen in lymphoproliferative responses to evaluate the cellular immune response. It was observed this peptide evokes lymphoproliferative and cytokine responses in individuals naturally exposed to the malaria parasite. The intensity of PBMCs proliferation was observed to be higher in sera obtained from P. falciparum exposed as compared to unexposed healthy individuals, suggesting earlier recognition of peptide of this region by T cells. Furthermore, the binding mode of HLA–peptide complex and their interaction may lead to a rational and selective peptide-based vaccine candidate design approach which can be used as a malaria prophylaxis.

Rice husk–Polypropylene (RH–PP) composites were prepared using four level of filler loadings (10, 20, 40 and 50%) incorporating maleic anhydride grafted Polypropylene (MAPP) and m-isopropenyl α–α-dimethylbenzyl-isocyanate grafted Polypropylene (m-TMI-g-PP) coupling agents. Mechanical properties of the composites indicated that m-TMI-g-PP coupling agent performed better than that of MAPP. Tensile and flexural properties of composites prepared with coupling agents were found to be superior to controlled samples. However, Impact strength of the composites decreased with increasing filler loadings in all the composites. Fourier transform infra red (FTIR) spectroscopy of the composites revealed effective coupling between rice husk and polypropylene. Scanning electron microscopy indicated improved adhesion between rice husk and Polypropylene in case of coupled composites. Thermal stability of pure PP was higher than that of rice husk and RH–PP composites. Use of coupling agent had no significant effect on thermal stability of the composites.

Dynamic modulus of elasticity (DMoE) of natural fiber reinforced high density polyethylene composites prepared with variety of fibers and their different proportions was determined using ultrasonic pulse propagation method. The DMoE was compared with the static modulus of elasticity as determined by both tensile and flexural test. The elastic modulus of the composites increased with the increasing fiber content irrespective of type of fiber. However, the incremental rate in modulus was varying with fiber type. Jute fibers resulted in maximum improvement whereas coir fibers reinforcement had marginal improvement in stiffness of the composites. The elastic modulus was theoretically modelled for all fiber types based on the elastic modulus of the fibers and HDPE and the model was effective in describing the change in modulus with increasing fiber content. There was a strong correlation between DMoE and static MoE (both tensile and flexural modulus). The ratio of DMoE to static MoE was found to vary with fiber content and smaller differences were observed in stiffer composites. This suggests that static MoE was influenced by the visco-elastic behaviour of HDPE and its composites at lower fiber content.

This research is focused on characterization, modelling and product designing from bamboo fiber reinforced polypropylene composite. Bamboo fiber of mesh size of − 80/+ 100 (180–225 μm) were blended with polypropylene in a twin screw extrusion system at different weight percentages of bamboo (10, 20, 30, 40, and 50%). In-house synthesized m-TMI-g-PP was used as the coupling agent. Mechanical characterization reveals a continuous increment in tensile strength, flexural strength and elastic modulus with increasing fiber content. At 50% bamboo content, tensile and flexural strengths increased by 36 and 64% respectively and elastic modulus increased by 300% with respect to virgin polypropylene. Scanning electron microscope images of the fractured surface of composite indicated effective wetting of bamboo fiber with polypropylene. Halpin–Tsai model was found to describe the relative modulus of the composites at different fiber content effectively. Macro mechanical approach in which the composite is assumed to be isotropic was used to simulate uniaxial tensile test. The simulation was performed using Hypermesh (a FEM preprocessor) and explicit solver LS-DYNA. The stress–strain behaviour predicted by material model MAT 24 was in close agreement with the experimental results. A portable toilet design is suggested from the developed composite material based on the simulation results.

In this study, bamboo fiber filled polypropylene composites (BPCs) were prepared using bamboo and coconut shell charcoal as reinforcing fillers for enhancing the properties of composites. Bamboo and coconut shell biomass were carbonized at different carbonization temperatures (300, 400, 600, and 900OC); 1 h soaking time and at 5OC−min heating rates. The effect of carbonization temperature and charcoal content (0.5%, 1.0% and 1.5%) on mechanical, thermal and water absorption properties of BPCs has been investigated. The experimental results show that charcoal which is obtained at lower pyrolysis temperature (300OC and 400OC) improves the strength properties of BPCs, whereas, strength properties remains unaltered when charcoal prepared at elevated temperatures (600OC and 900OC) are added to BPCs. Compared to coconut shell charcoal (CSC) better mechanical properties were obtained through bamboo charcoal (BC). This has been attributed to flakes like appearance of BC, having pores present on their surfaces. The study also shows that addition of charcoal provides thermal stability to BPCs, particularly via charcoal prepared at elevated temperature (900OC). The optimum temperature for achieving sufficient hydrophobicity in BPCs is found to be 300OC and 600OC for BC and CSC, respectively.

Dynamic modulus of elasticity (DMoE) of wood polymer composites, prepared with varying proportion of wood content, was determined using flexural vibration and ultrasonic pulse transit time methods. The DMoE was compared with the flexural modulus as measured by standard three point bending test. The elastic modulus of the composite increased with the increasing fiber content. Both vibration methods exhibited a strong linear association with static modulus. DMoE by ultrasonic pulse method was higher compared to flexural vibration method at low wood content and the difference diminished at 50% wood in composites. Both the dynamic modulus were higher as compared to the static modulus at all fiber loadings, however the difference between dynamic and static modulus reduced non-linearly with increasing wood content.

Plasmodium falciparum erythrocyte membrane protein-1 (Pfemp-1), a variant adhesion molecule, can act as a key component of immunity against malaria. In the current selection of malaria vaccines, no efficient vaccines are available that can be employed for its proper treatment. Unfortunately, resistance to post-infection treatments is increasing and therefore there is a pressing need to develop an efficient vaccine. Peptide-based vaccines can be effective tools against malaria but HLA restriction is a major hindrance which can be conquered by using promiscuous peptides. In this work, we employed a combined in silico and experimental approach to identify promiscuous peptides for the treatment of malaria. At first, using the immunoinformatics approach, promiscuous peptides were predicted from two conserved domains, CIDR-1 and DBL-3γ, of the Pfemp-1 antigen. These peptides were selected on the basis of their predicted binding affinity with different HLA class-I & class-II alleles. A total of 13 peptides were selected based on their predicted IFN-γ and IL-4 induction ability as well as their hydrophobicity. Out of these 13, the peptide C6 was synthesised and experimentally evaluated for further rationalization, HLA-peptide complex modelling and binding interaction analysis. Interestingly, the peptide C6 (SFIHIYLYRNIRIQL) showed an encouraging immunological response and T-cell proliferation in the immunological assay. This valuable content can aid the better design of more potent and selective vaccine candidates against infectious diseases.

The effectiveness of m-isopropenyl-α,α-dimethylbenzyl isocyanate-grafted-polypropylene ( m-TMI-g-PP) as a coupling agent was evaluated for wood flour filled polypropylene composites. The performance was compared with the conventionally used maleic anhydride grafted polypropylene (MAPP) coupling agent in terms of mechanical properties. Rubberwood flour filled polypropylene composites were prepared at varying proportion (1 wt% to 9 wt% of wood fibers) of m-TMI-g-PP and MAPP coupling agents. Composites with m-TMI-g-PP coupling agent exhibited consistently superior strength properties as compared to MAPP at all concentrations of coupling agents inferring that m-TMI-g-PP is a better coupling agent. About 6–9 wt% coupling agent with respect to wood fiber was found to be the optimal level of coupling agent. The effect of filler content and fiber dimension on the properties of composites with m-TMI-g-PP coupling agent was also studied. Tensile strength, flexural strength and tensile modulus increased with increasing filler content in the composites with the coupling agent. At 50% filler loading, composites with coupling agent exhibited about 50%, 78% and 270% improvement in tensile strength, flexural strength and tensile modulus, respectively, over virgin polypropylene. Fiber aspect ratio was found to have a significant effect on the tensile strength of the composites.

The dimensional stability and mechanical properties of radiata pine (Pinus radiata) has been investigated after thermo-mechanically compression (TMC) followed by oil heat-treatment (OHT). Wood specimens were first compressed in the radial direction then heat-treated in a linseed oil bath at 160–210°C. Spring-back percentage, water repellence efficiencies, and compression set recovery percentage were determined as indicators of dimensional stability. The resistance of treated wood against a brown rot fungi was assessed based on an accelerated laboratory fungal decay test. Strength, stiffness and hardness were determined as a function of different treatment parameters. After TMC, high compression set (39%) was achieved without any surface checks and cracks. Specimens undergoing TMC followed by OHT showed relatively less swelling and low compression set recovery under high moisture conditions. The fungal resistance of wood after TMC+OHT slightly increased compared to untreated wood and TMC wood. The mechanical properties of TMC+OHT wood were inferior to those of TMC wood.

Biopolymers have received much attention of researchers due to concerns over disposal of plastics, greenhouse gas emission and environmental problems associated with it. Polylactic Acid (PLA) is one of the thermoplastic biopolymer made from lactic acid by using agricultural resources. PLA has received significant interest due to its competitive properties when compared to commodity plastics such as Polyethylene, Polypropylene and Polystyrene. PLA has interesting properties such as high stiffness, UV stability, clear and glossy finish. However, application of PLA is restricted due to its brittle nature. Engineering and thermal properties of PLA can be improved by reinforcing fibres and fillers. Lignocelluloses or natural fibres such as Jute, Hemp, Bamboo, Sisal and Wood fibres can be used as reinforcement. By using natural fibres, a very bio-compostable composite can be produced. In the present study, short fibres from Melia Dubia wood were extracted and used as reinforcement to PLA Bio-Polymer matrix. Characterization of developed composite was obtained using tensile and flexural tests. Tensile test simulation of composite was performed using Altair Hypermesh, a Finite Element (FE) preprocessor and LS-Dyna an explicit FE solver. MAT_01, an elastic material model in LS-Dyna was used to model the behaviour. Further, the design of Root Trainer using developed composite has been explored. A Root Trainer is an aid to the cultivation of seedlings in nurseries. Root Trainer made by using developed composite has advantage of biodegradability and eco-friendly nature.

The use of dynamic mechanical analysis was explored as a possible method of screening for wood quality in breeding programmes. Viscoelastic properties along the grain of wood from 18-month-old Pinus radiata saplings were measured using a humidity-controlled dynamic mechanical analyser. Storage modulus and tanδ were determined independently for opposite wood (OW) and compression wood (CW) in 25 trees in the temperature range from 10 to 45 °C at 5 °C intervals at three frequencies (0.1, 1 and 10 Hz) at constant moisture content of 9 %. Storage modulus and tanδ were frequency and temperature dependent. The two wood types did not differ significantly in their storage modulus. But OW exhibited significantly higher tanδ values than CW. The relationship of viscoelastic properties with physical (acoustic velocity, basic density and longitudinal shrinkage) and chemical wood properties was explored. There was a strong correlation (R = 0.76) between storage modulus and dynamic MOE (measured by acoustics). In addition, tanδ was positively correlated with longitudinal shrinkage. Monosaccharide compositions of the cell wall polysaccharides and lignin contents were determined and showed significant differences in the relative proportion of major cell wall components in OW and CW. Correlations between tanδ and xylose, originating from heteroxylans, and lignin content were found for CW, suggesting that the damping behaviour of cell walls is controlled by the matrix between cellulose fibril aggregates.

Hydrophilic nature of ligno-cellulosic fibers can affect dimensional stability and interfacial bond strength of wood polymer composites. In this paper, moisture adsorption and absorption behaviour of bio-fiber filled high density polyethylene composites has been reported. Composites were prepared with wood pulp and bamboo flour at varying filler concentration and subjected to moisture adsorption and absorption. The magnitude of moisture absorption and adsorption increased with increasing filler content. Moisture adsorption in wood fiber based composites was higher than bamboo flour but there was no significant difference in their water absorption behaviour. Use of coupling agent exhibited a significant influence on the magnitude of water absorption by the composites. Composites with coupling agent absorbed 25–40 % less moisture as compared to the composites without coupling agent in both filler types. Moisture absorption behaviour in the composites was explained based on the theoretical Fickcian diffusion model.

Wheat crop may experience heat stress during post-anthesis phase associated with oxidative stress, enhanced senescence, and reduced productivity. Stay green is a desirable character for the selection for heat tolerance in wheat. In the present study, antioxidant metabolism was studied under post-anthesis heat stress in field during monocarpic senescence by comparing two wheat genotypes, namely Hindi62 (heat tolerant and delayed senescent) and PBW343 (heat susceptible and early senescent). Hindi62 exhibited lesser oxidative stress, membrane damage, and coordinated antioxidant defense as compared to PBW343 under heat stress during post-anthesis stage. Higher activity of SOD, CAT, APX, GR, and MDHAR under heat stress contributed towards delayed senescence in Hindi62 compared to PBW343. GSH/GSSG ratio was also maintained at higher level in Hindi62 under heat stress compared to PBW343 during senescence. Hence, the present study clearly shows that upregulated level of the total antioxidant capacity during grain development contributed towards delayed senescence and heat tolerance in Hindi62 compared to the heat-susceptible PBW343.

Lantana camara is a small perennial shrub species, native to central and South America. The species has established itself in agricultural fields as well as in forest areas of India and has become dominant weed crowding out native species and reducing bio-diversity. So far, Lantana has very limited commercial uses like furniture making and as a source of energy. In order to get rid of its invasion to forest and agricultural areas, it has to be utilized at the industrial scale. Using lantana stems as the source of lignocellulosic fiber in thermoplastic composites is one the potential applications. In this study, Lantana flour-filled polypropylene composites were prepared. Lantana stems were cut, chipped into smaller size, dried and pulverized to get the fine powder. Lantana flour was compounded with polypropylene in a twin-screw extruder using maleic anhydride-grafted polypropylene as the coupling agent. Composites were prepared at varying fiber loading from 10 to 50%, and mechanical properties were investigated. The mechanical tests indicated that the tensile and flexural strength properties increased with the increase in the fiber loading percentage in case of coupled composites. The presence of bark in lantana flour had no significant influence on the strength properties of composites. The properties of lantana-filled composites were found to be comparable with wood and bamboo fiber-filled composites. The study clearly demonstrates the potential utility of lantana stems for wood polymer composites.

Logs of many fast-grown tree species develop end splitting immediately after felling, and timber from such logs suffers from excessive warping and twisting on sawing. Such distortions are attributed to the presence of high magnitude of inherent growth stresses. This results in low recovery of quality sawn material and therefore devalues a tree species for timber purposes. For the efficient utilization of any timber species, prior knowledge on the intensity and distribution of growth stresses in trees is vital. Melia dubia is increasingly gaining popularity as the plantation species because of its fast growth and is becoming a preferred species for plywood manufacturing. For ensuring the suitability of the species as a timber for other applications, the propensity of growth stresses needs to be known. Since inherent growth stresses cannot be measured directly, in lieu longitudinal growth strains are measured by relieving the stresses. In this paper, magnitude of longitudinal growth strain measured in trees and logs of M. dubia from three age groups growing in different locations are presented. The longitudinal growth strains were measured using wire strain gauge method. The magnitude of growth strain was ranging from 56 to 730 microstrains. The observed growth strains are in the range which does not raise a serious concern in processing and utilizing this species as timber.

The surface growth stress in logs can be determined by slitting the log axially and measuring the outward deflection of the two halves. The saw kerf removes stressed material which generates a compressive strain in the remaining material and thereby reduces the surface growth stress. The purpose of the work is to establish the magnitude of this error. The analysis assumes a uniform compressive stress in the core of the log and a logarithmic distribution in the outer region. The total axial force in the kerf before removal is calculated and, from this, the stress change in the material remaining after kerf removal is derived. Data are presented for a range of kerf widths and for three different growth stress distributions. Direct measurement of the kerf removal error was made by direct measurement of the contraction of the log and by strain gauges to measure the strain. The measured values were close to the calculated values for three growth stress distributions. The analysis yields acceptable valu...

Assessment of natural variability in morphological and important wood quality traits and selection of trees with superior or desired wood characteristics is a prerequisite for an effective tree improvement. Variability in morphological and wood quality traits was assessed in selected trees from a 9-year-old plantation of Melia dubia raised from material of unknown genetic source. A large variation was observed in vertical and lateral tree growth within the sampled trees. Wood quality traits namely heartwood proportion, basic density, stress wave velocity, dynamic modulus of elasticity (DMoE) and volumetric shrinkage also exhibited a substantial variation between trees. Pilodyn penetration exhibited a strong negative correlation with wood basic density and DMoE. Acoustic velocity in trees, wood basic density, and volumetric shrinkage did not exhibit any significant relationship with each other. Similarly, tree growth parameters were not related to either wood density or shrinkage. Acoustic velocity measured in standing trees by transit-time method was in a close agreement with the velocity measured in logs using resonance method. A large variability in the measured traits and absence of any significant relationship in morphological and wood quality traits imply that selection of trees with superior wood properties can be made for further propagation without compromising on tree growth. Pilodyn and acoustic velocity measurements in standing trees provided an opportunity to screen and select M. dubia trees with superior wood density and modulus of elasticity.

Wood physical and mechanical properties in seven tropical hardwood species viz., Acacia auriculiformis A. Cunn. ex Benth., Artocarpus hirsutus Lamk., Artocarpus heterophyllus Lamk., Swietenia macrophylla King, Xylia dolabriformis Benth., Hevea braziliensis (H.B.K.) M. A.), and Tectona grandis L.f. have been studied by means of destructive and non-destructive techniques (NDT). Mechanical strength properties and specific gravity were evaluated by conventional methods. NDT was carried out by a Pilodyn and Treesonic Microsecond Timer (TMT) to measure a steel pin penetration depth into wood and dynamic MOE, respectively. In focus was the question, whether NDT data are suitable predictors for physical and mechanical properties of the indicated hardwood species. Dynamic MOE obtained by TMT correlated strongly positive with all the strength properties studied, except shearing stress. TMT data also correlated very well to static bending MOE and MOR. A linear relationship was found between Pilodyn steel pin penetration depth and oven dry specific gravity in all the species. Both Pilodyn and TMT proved to be useful predictors of timber properties, and these instruments have a high potential for timber grading.

A search is presented for physics beyond the standard model in final states with two opposite-sign, same-flavor leptons, jets, and missing transverse momentum. The data sample corresponds to an integrated luminosity of 2.3 fb−1 of proton-proton collisions at [Math Processing Error]s=13 TeV collected with the CMS detector at the LHC in 2015. The analysis uses the invariant mass of the lepton pair, searching for a kinematic edge or a resonant-like excess compatible with the Z boson mass. Both search modes use several event categories in order to increase the sensitivity to new physics. These categories are based on the rapidity of the leptons, the multiplicity of jets and b jets, the scalar sum of jet transverse momenta, and missing transverse momentum. The observations in all signal regions are consistent with the expectations from the standard model, and the results are interpreted in the context of simplified models of supersymmetry. BMWFW and FWF; FNRS and FWO; CNPq, CAPES, FAPERJ, and FAPESP; MES; CERN; CAS, MOST, and NSFC; COLCIENCIAS; MSES and CSF; RPF; SENESCYT; MoER, ERC IUT and ERDF; Academy of Finland, MEC, and HIP; CEA and CNRS/IN2P3; BMBF, DFG, and HGF; GSRT; OTKA and NIH; DAE and DST; IPM; SFI; INFN; MSIP and NRF; LAS; MOE and UM; BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI; MBIE; PAEC; MSHE and NSC; FCT; JINR; MON, RosAtom, RAS and RFBR; MESTD; SEIDI and CPAN; Swiss Funding Agencies; MST; ThEPCenter, IPST, STAR and NSTDA; TUBITAK and TAEK; NASU and SFFR; STFC; DOE and NSF. Individuals have received support from the Marie-Curie program and the European Research Council and EPLANET; the Leventis Foundation; the Alfred P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture; the Agentschap voor Innovatie door Wetenschap en Technologie; the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Science and Industrial Research, India; the HOMING PLUS program of the Foundation for Polish Science, cofinanced from European Union, Regional Development Fund, the Mobility Plus program of the Ministry of Science and Higher Education, the National Science Center, contracts Harmonia 2014/14/M/ST2/00428, Opus 2013/11/B/ST2/04202, 2014/13/B/ST2/02543 and 2014/15/B/ST2/03998, Sonata-bis 2012/07/E/ST2/01406; the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF; the National Priorities Research Program by Qatar National Research Fund; the Programa Clarín-COFUND del Principado de Asturias; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its 2ndCentury Project Advancement Project; and the Welch Foundation.

Background: Distal femoral fractures represent a challenging problem in orthopaedic practice. Open reduction with internal fixation has replaced previous trends of closed conservative management and external fixation. Distal femoral locking compression plate (DF-LCP) provides both locking and compression screw fixation of the femur shaft. This study was conducted to assess the clinical and radiological results of distal femoral fractures treated with DF-LCP.Methods: It was a prospective study on 90 cases. Fracture patterns AO type A and C were considered. Lateral approach was used as standard surgical technique. The total follow up period was 6 months .Functional and radiological results were evaluated using Neer’s score.Results: The series consisted of 64 males and 26 female patients with mean age 40.56 years. Road traffic Accident (68%) was the commonest mode of injury. Most were closed fractures. Wound infection was seen in 4 patients. Average flexion at knee joint was 117°. 100% union rate was observed with an average union time of 14.3 weeks. NEER’s score was excellent in 44, good in 32, fair in 10 cases and poor in 4 cases.Conclusions: DF-LCP is an important armamentarium in treatment of distal femur fractures especially when fracture is closed, severely comminuted and in case of osteoporosis.

Bio-based fibers (wood and bamboo)-filled high-density polyethylene composites were prepared in a twin-screw extruder using two types of coupling agents: maleated polyethylene and glycidyl methacrylate-grafted polyethylene. The effect of bio-fibers used as filler on the mechanical properties of composites was studied. It was observed that mechanical properties such as tensile and flexural strengths of the composites with coupling agent increased with increasing filler loadings. Tensile strength and flexural strength exhibited improvement up to 66% and 90%, respectively, over virgin high-density polyethylene. The maximum enhancement in the properties was observed with wood pulp when compared with wood- or bamboo flour-filled composites. Effect of coupling agents on the performance of composites was evaluated at 30% filler loading with wood flour as the filler. The study suggested that glycidyl methacrylate-grafted polyethylene exhibited better tensile and flexural properties as compared with maleated polyethylene. Impact strength of the composites prepared with coupling agent was found to be more than uncoupled composites. Among the fiber type, the impact strength of wood-fiber-filled composites was superior than that of bamboo flour-filled composites. Moisture absorption study indicated that even at 40% filler loading, moisture gain by the wood fiber- and bamboo flour-filled composites was merely 1.55% and 2.60% after 600 h of water immersion test, which suggests encapsulation of filler material by the polymer matrix.

Coir fiber and polypropylene (PP) composites were prepared using m-isopropenyl-α-α-dimethylbenzyl isocyanate grafted polypropylene as a coupling agent. The effect of concentration of coupling agent on mechanical properties (tensile, flexural and impact) was investigated and discussed. The mechanical tests indicate that tensile and flexural strength increases with increase in concentration of coupling agent. The optimum loading capacity of coupling agent was 5 %. Increase in tensile and flexural strength may be attributed to improved wetting and interaction between PP and coir fiber. However, their was no effect of coupling agent concentration on tensile or flexural modulus. The impact strength of composite was also investigated which showed that notched impact strength reduces with increase in coupling agent concentration, while un-notched impact strength increases with increase in coupling agent concentration.

We studied the variability in longitudinal growth strains and wood basic density in five-year old trees from five clones (one tree per clone) of Eucalyptus tereticornis. Mean longitudinal growth strain in clones ranged from 466 to 876 μm. There was a significant difference between clones in growth strains and wood basic density. Clone 10 exhibited maximum growth strains and basic density, whereas clone 3 and clone 7 exhibited minimum growth strains and basic density, respectively. Within a tree, the growth strain variation with tree height was high but statistically insignificant while within tree variation in basic density was very small. There was no specific trend in variation in either strain or density within a tree. There was 5%–200% difference in growth strain on opposite sides of the logs. However two strains showed a strong positive correlation. There was a moderate positive association of wood basic density and mean growth strains in logs. The variation around the periphery emphasize the need to measure strain more than one, preferably on opposite sides at the same height, on a tree to know the mean strain level for the purpose of selection of clones.

m-Isopropenyl-α, α-dimethylbenzyl isocyanate (m-TMI) was grafted on isotactic polypropylene (PP) using di-cumyl peroxide as a reaction initiator under varying reaction conditions to yield m-TMI-g-PP coupling agent with four sets of grafting yield and molecular weight. Grafting yield of the synthesized m-TMI-g-PP were 1.80%, 2.01%, 9.05%, and 8.86% and molecular weight of the corresponding grafted polymer were 1,129,225; 187,240; 124,130; and 180,838, respectively. Rubberwood flour reinforced polypropylene composites were prepared using these coupling agents and tested for mechanical properties. m-TMI-g-PP coupling agent with 9.09% grafting and 124230 Mw was found to give the highest tensile and flexural strengths. Flexural modulus of the coupled composites was higher than uncoupled composites. Interfacial region of the composites characterized by scanning electron microscope (SEM) suggest effective wetting of fiber by PP in the case of coupled composites. The effect of fiber loading on composites indicates continuous increment in tensile and flexural strengths in coupled composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44196.

Key message Acoustic techniques can be utilised to rank a large population of young trees for stiffness and stability for breeding purposes. Introduction This study sought to validate new approaches to rapid, very early screening and selection of radiata pine families, using microfibril angle (MFA) as a reference for comparative purposes. Method A key feature was tilting the trees at an angle of ∼30° after the initial 12 months of growth in order to force production of opposite wood (OW) and compression wood (CW) and prevent the co-mingling of the two distinctive wood types as occurs ‘at random’ within vertical stems. After 34 months, OW and CW materials were characterised independently for acoustic velocity (V), dynamic modulus of elasticity (MOEdynamic), basic density and longitudinal shrinkage. Finally, MFA were determined with X-ray diffraction. Result No phenotypic correlation was observed between OW and CW wood properties. The Spearman ranking correlation between V2 and MFA values in OW was 0.81. Conclusion We show that families or individual trees with superior wood properties can be screened at this young age using acoustics. Further, the same outcomes can be achieved as with X-ray diffraction (MFA) but more cheaply and rapidly.

This paper deals with preparation of nanocomposites using modified nanoclay (organoclay) and polypropylene (PP), with, and without compatibilizer (m-TMI-g-PP) to study the effects of modified nanoclay and compatibilizer on viscoelastic properties. Nanocomposites were prepared in two steps; compounding of master batch of nanoclay, polypropylene and m-TMI-g-PP in a torque rheometer and blending of this master-batch with polypropylene in a twin-screw extruder in the specific proportions to yield 3-9% nanoclay by weight in the composite. Dynamic Mechanical Analysis (DMA) tests were carried out to investigate the viscoelastic behavior of virgin polypropylene and nanocomposites. The dynamic mechanical properties such as storage modulus (E'), loss modulus (E `') and damping coefficient (tand) of PP and nano-composites were investigated with and without compatibilizer in the temperature range of -40 degrees C to 140 degrees C at a step of 5 degrees C and frequency range of 5 Hz to 100 Hz at a step of 10 Hz. Storage modulus and loss modulus of the nano-composites was significantly higher than virgin polypropylene throughout the temperature range. Storage modulus of the composites increased continuously with increasing nano-content from 3% to 9%. Composites prepared with compatibilizer exhibited inferior storage modulus than the composites without compatibilizer. Surface morphology such as dispersion of nanoclay in the composites with and without compatibilizer was analyzed through Atomic Force Microscope (AFM) that explained the differences in viscoelastic behavior of composites. (C) 2011 Elsevier Ltd. All rights reserved.

Drying of wood has become one of the most important aspects in modern wood industry scenario as it improves the quality of wood by many folds. Different methods have been tried to dry wood. Microwave drying is one of the most efficient methods of drying materials. In this study, drying behaviour of silver oak wood (Grevillea robusta) planks using a 2.4 kW intensity microwave dryer is presented. Effect of microwave time, auxiliary heating, plank thickness is studied to assess drying rate and any defects arising due to microwave heating. The amount of water lost increased linearly with microwave exposure time. On an average, moisture loss rate was about 13 g/min at 2 kW microwave power. There was no significant effect of initial moisture content on moisture loss rate from wood. Auxiliary heating was found to aid in accelerating drying rate however it also contributed substantially in energy consumption during drying. Thicker sections of wood exhibited slightly slower drying than thinner sections. Wood exposed to microwave for different period did not exhibit any remarkable difference in their subsequent air-drying rate.

This paper presents a new approach to assess wood quality in 1-year-old Eucalyptus regnans F. Muell. Twenty-two seedlings were grown tilted to induce tension wood and acoustic velocity, basic density, longitudinal shrinkage, and volumetric shrinkage of both opposite wood and tension wood were assessed subsequently. Longitudinal growth strains were also estimated in the leaning stems by sawing along the length through the pith and measuring the bending of the two halves. The derived longitudinal growth strain, which varied from 708 to 2319 µε, was uncorrelated with stem and wood characteristics. Wood characteristics differed significantly between upper-side wood (predominantly tension wood) and lower-side wood (opposite wood). Tension wood was characterized by a higher acoustic velocity (high stiffness), basic density, and volumetric shrinkage compared with opposite wood. Tension wood also exhibited significant collapse and dimensional distortion such as twisting. Longitudinal shrinkage exhibited a significant negative relationship with acoustic velocity in opposite wood and a positive relationship with the basic density in tension wood. This new approach has potential in early selection of breeding material with superior normal wood properties from 1-year-old material by isolating the influence of tension wood. This approach can also be useful in understanding the variability in propensity of tension wood production in breeding populations.

The long time frame for evaluating selection candidates is a major barrier to the deployment of genetic gain from tree breeding programs. This situation is compounded in wood quality studies by constraints on the number of sampled individuals when trees are older and larger. This paper documents the degree of genetic control and genetic association for wood quality traits in 18-month-old leaning Pinus radiata seedlings. Trees were separately assessed for basic density, green and dry acoustic velocity, and longitudinal and volumetric shrinkage in opposite and compression wood. Heritability estimates were low to moderate for both compression and opposite wood (ranging from 0.15 to 0.38). Estimated genetic correlations were very high in opposite wood, where green velocity displayed the highest correlations with both longitudinal (−0.89) and volumetric (−0.64) shrinkage, closely followed by dry velocity. These correlations were substantially lower for compression wood. The estimated correlations between compression and opposite wood characteristics were high for most traits except for longitudinal shrinkage. We suggest how these results could be used for very early screening for wood stiffness and dimensional stability. We propose that information on early genetic control of wood quality and the methodologies used to elicit it should be integrated in breeding and deployment programs.

Background: The objective of the study was to evaluate the functional outcome of arthroscopic reconstruction of ACL tear using triple layered PLT autograft and to study its effect on ankle stability.Methods: The study included 25 patients. The range of age was 18-42 years. Pre-op clinical tests and MRI was done to confirm tear. Reconstruction was done arthroscopically. Physiotheraphy protocol was fixed for all patients. Final outcome was assessed at 6 months using IKDC score and ankle stability was assessed by grading muscle power (MRC grading) with the normal side as control.Results: IKDC score was normal or near normal in 21 patients and only 4 patients were rated as abnormal or severely abnormal. Mean IKDC Score was 83.53. Stability of the ACL was assessed using the Lachman test: normal in 18 cases (72%), 1+ laxity in 5 cases (20%), 2+ and 3+ in 1 case (4%) each. Pivot shift was negative in 15 cases (60%), Pivot glide was seen in 9 cases (36%) and gross pivot shift was seen in 1 patient. Partial meniscectomy of the medial meniscus was performed in 5 patients. No patient experienced ankle dysfunction however 2 patients had pressure pain in the region of the graft harvest.Conclusions: PLT graft is similar to the native ACL both in terms of thickness and strength. It can be an appropriate autograft option for ACL reconstruction without compromising ankle function and avoiding potential complications of hamstring and BPTB autograft obtained from the knee region.

Background: Clubfoot is a complicated deformity of the foot. It is one of the commonest congenital deformities in children. The main aim of this study was to evaluate the efficacy management of clubfoot by Ponseti method.Methods: This prospective study included 300 children (456 club feet) below the age of 2 years with idiopathic clubfeet from January 2013 to December 2017. In all the cases the Ponseti method was used for the management. The severity of the deformity was assessed with the help of the Pirani score and clinical evaluation of the foot was done.Results: Out of 300 patients 204 patients were male and 96 patients were female and 144 were unilateral clubfoot and 156 were bilateral cases of clubfoot. The mean number of casts required for correction was 5.4 (4–10). Out of 456 clubfeet 356 (78%) feet were required tenotomy. There was relapse seen in 36 (7.9%) feet which had to be managed with 2–3 serial manipulations and casting and these resolved. Excellent result found in our study in 92% cases, good results were found in 5% cases and poor results were found in 3% cases.Conclusions: Ponseti technique is a very useful and effective method of management of idiopathic clubfoot up to 2 year of age.

The damping coefficient (tanδ) of wood flour filled polypropylene composites, having varying filler concentrations were measured using the free vibration decay of disk-shaped specimen, vibrating in flexural vibration mode. The damping coefficients decreased with the increase of filler load in composites. There was no significant difference in damping behavior of composites with and without compatiblizer at low filler level (upto 30%). At higher filler loading (>30%), composites with compatiblizer had lower damping coefficient suggesting improved interfacial adhesion between wood and polypropylene. The damping in composite is attributed to the damping because of the composite constituents and damping at the interface. The damping because of interface was estimated using a model and was found to increase with the increase in filler loading. At higher filler content, damping due to interface in composites with compatiblizer was significantly lower than in composites without compatiblizer suggesting a better interfacial adhesion between the wood filler and polypropylene matrix with compatiblizer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009