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Apical hook formation is essential for the emergence and stand establishment of cotton plants. Searching for agronomic measures to regulate apical hook formation and clarifying its mechanism are important for full stand establishment in cotton. In this study, cotton seeds were sown at varying seeding rates or depths in sand to determine if and how apical hook formation was regulated by seeding rates or depths. The results showed that deep seeding or low seeding rates increased mechanical pressure and then increased ethylene content by increasing GhACO1 and GhACS2 expression to improve apical hook formation. Silencing of the GhACO1 and GhACS2 genes or exogenous application of 1-methylcyclopropene (1-MCP) decreased the ethylene content and inhibited apical hook formation in the cotton seedlings. Deep seeding, a low seeding rate, or 1-amino cyclopropane-1-carboxylic acid (ACC) treatment increased the expression of GhHLS1 and GhPIF3 genes, but their expression was decreased in theVIGS-ACO1 and VIGS-ACS2 seedlings. Silencing of the GhHLS1 and GhPIF3 genes inhibited apical hook formation, although the expression of GhACO1 and GhACS2 was unchanged. GhPIF3 may act upstream of GhHLS1, as the expression of GhPIF3 in the VIGS-HLS1 seedlings was unchanged, while the expression of GhHLS1 in the VIGS-PIF3 seedlings decreased. These results suggested that raised mechanical pressure could increase ethylene content by inducing GhACO1 and GhACS2 gene expression, which promoted apical hook formation by increasing the expression of GhHLS1. Therefore, adjusting the mechanical pressure through changing the seeding depth or seeding rate is an important means to regulate apical hook formation and emergence.

Li metal anodes as one of promising anodes in next-generation batteries, face the challenges from infinite volume change and high reactivity to electrolytes that easily leads to unstable Li/electrolyte interface and unique dendrite growth of Li. Although mechanical pressure can effectively inhibit the dendrite growth of Li, it also increases the risk of short circuits, because Li metal easily grows into the separator under pressure. Here, an interface layer is introduced on Li metal to block this growth, using Li3P/LiCl as a model. Meanwhile, the dense and robust layer also reduce the side reactions between Li and electrolytes. With the helps from mechanical pressure and interface layer, this design exhibits the improved electrochemical performances, much better than that without pressure or without the layer. The full cells of Li3P/LiCl-coated Li//LiFePO4, show a capacity of 1.69 ​mAh cm−2 after 1000 cycles under pressure at 3.9 ​mA ​cm−2 with a capacity retention of 99.5% in carbonates. The results indicate the promising potential for the pressure effect to be used for advanced Li metal anodes.

A novel multiphase mesh-free particle numerical model is developed and applied for modeling of sub-aerial (dry) and submerged (underwater) landslides. The model is based on the weakly-compressible moving particle semi-implicit method (WC–MPS), and treats the multiphase system of water and granular materials as a multi-density multi-viscosity continuum. The viscous behaviour of the granular material is predicted using a visco-plastic rheological model (i.e. μ(I)) with a dynamic inter-grain mechanical pressure. The model is validated and evaluated for the rigid, sub-aerial and submerged landslides in comparison with the available experimental measurements and past numerical results. The granular surface profile and the evolution of the granular mass are compared. Comparisons show a good agreement between the results of the developed model and those of the experiments, and also a better accuracy comparing to the past numerical studies. The results also show the capability of the model in dealing with the shape evolution and the deformation and fragmentation of granular interface. Complementary experiments on the sub-aerial landslide are also conducted to study the relevant physics and validate the model. The role of the rheological model is also investigated. Comparing the μ(I) rheology with the widely–used Herschel–Bulkley model shows a slightly more accurate granular profiles for the μ(I) rheology, for both sub-aerial and submerged landslides.

Inspiratory muscle training improved maximal inspiratory pressure (MIP) and vagal-mediated heart rate variability (HRV) in older women. However, it is unknown what occurs if the training is discontinued (detraining protocol). The aim of this study was to investigate the IMT and detraining effects on resting HRV in older women. Twelve healthy older women (60–72 yrs) enrolled in home-based IMT at 50% MIP (IMT-group) or placebo at 5% MIP (Sham-group) protocol for 4 weeks using a mechanical pressure threshold loading device. The participants were not engaged in any other exercise protocol at that time. During IMT and Sham interventions, the inspiratory load was adjusted weekly by the actual MIP and resting heart rate variability (HRV) evaluated. After training cessation (4 weeks of detraining), participants returned to the lab for HRV and MIP recordings. Adherence to IMT was superior to 95%. IMT increased MIP (23 ± 8 cmH2O) and vagal-mediated HRV (normalized HF; 37 ± 8%), following by the reduction of sympatho-vagal balance (LF/HF), from the second week to the end of the protocol compared to sham-group. After detraining, IMT-group reduced MIP (−23 ± 8 cmH2O) and vagal-mediated HRV (normalized HF; −38 ± 14%) returning to baseline values. In conclusion, MIP and vagal-HRV improvements induced by IMT were reversed by four weeks of detraining.

Dense CsAlSi 5 O 12 was successfully obtained by hot pressing of Cs-exchanged clinoptilolite at 900 °C. Simultaneous application of high temperature and mechanical pressure allowed formation of CsAlSi 5 O 12 at temperature considerably lower than 1150 °C which was the lowest reported temperature of CsAlSi 5 O 12 formation in pressureless sintered Cs-exchanged clinoptilolite. CsAlSi 5 O 12 formation was preceded by complete amorphisation of Cs-exchanged clinoptilolite in temperature range between 700 and 900 °C. Bearing in mind that clinoptilolite possesses high affinity for Cs cation it is believed that hot pressing of Cs-exchanged clinoptilolite might be an efficient way to immobilize radioactive Cs by its incorporation into crystal lattice of stable CsAlSi 5 O 12 . The samples sintered at 950 °C had relative density about 84% of theoretical density and open porosity of only 6% which is expected to result in low Cs leaching rate.

The development of sensing technologies has increased the intelligence level of equipment. It is difficult for traditional sensing technologies to meet many current application requirements, such as complex trajectory monitoring, flexible manufacturing or other fields. Triboelectric nanogenerators were first invented in 2012 and have revolutionized energy generation and sensing. Triboelectric sensors have a variety of structures, which have promoted their applications in the field of internet of things, biomedicine, intelligent transportation and motion sensing or something. The development of triboelectric nanogenerators in machinery industry has attracted wide attention. This review covers recent progress in the development of triboelectric mechanical sensors for monitoring mechanical motion, mechanical vibration, mechanical pressure and mechanical tactile perception. The prospects of triboelectric mechanical sensors are then summarized.

Unanticipated a new and simple urea-ammonium chloride cocrystal synthesis method on industrial scale was found during attempts to produce a kind of granulated compound fertilizer. The aggregation of fertilizer powder can make the interaction among particles from loose to close, which generate mechanical pressure and in turn act as the driving force to benefit cocrystal growth. Additionally, the honeycomb-like channels constructed by other coexisting compound make the water evaporates more moderate, which can help the formation of supersaturated solution at suitable rate, further promote the growth of cocrystal. This approach possibly opens a new route toward the developing methodologies for cocrystal synthesis.

Armillaria mellea and A. solidipes are two of the primary causal agents of Armillaria root rot (ARR) in over 500 woody hosts. Although extensive research on this disease has been conducted over the past few decades, finding controls for ARR has been challenging. This is largely due to the lack of knowledge of the fungal infection and host response processes. It is important to understand the infection process in order to develop new strategies to control the disease. In this review, the initial steps of the infection process of A. mellea and A. solidipes are discussed, with focus on fungal attachment and penetration. A mucilaginous substance produced at the rhizomorph tip is thought to aid attachment of the pathogen to host. Toxins and cell wall degrading enzymes produced by the fungus together with mechanical pressure generated by the rhizomorph is speculated to support fungal penetration. However, a detailed description of the Armillaria spp. infection process is lacking in the literature, and this illustrates the need for further studies.

The aim of this study was to investigate the age-related changes in the articular disc, condyle, condylar fibrocartilage, and subchondral bone of the temporomandibular joint (TMJ) in rabbits.Female New Zealand white rabbit aged 1, 4, 12, and 32 weeks were obtained. Each age group comprised 5 rabbits and was subjected to chondrocyte culture, histological assessment of the articular disc length, assessment of the anteroposterior diameter of the condyle, measurement of the fibrocartilage thickness, and assessment of the subchondral bone architecture. The production of Collagen, type II, alpha1 (COL2A1); SOX9; Collagen, type X, alpha1 (COL10A1); and Runt-related transcription factor 2 (Runx2) was detected via western blot. Six rabbits at the ages of 12 and 32 weeks were sacrificed for the mechanical pressure loading test (75 kPa, 3 days). Changes in the condyles after pressurization were observed via scanning electron microscopy and evaluated by micro-CT.Significant enlargement of the condyle occurred from 4 to 12 weeks of age (p = 0.003); however, the length of the articular disc increased significantly from 1 to 12 weeks of age (p 0.005). A rapid decrease in the cartilage thickness but an increase in the subchondral bone density occurred from 1 to 4 weeks of age and from 4 to 32 weeks of age in rabbit, respectively (p 0.05). The expressions of COL2A1 and SOX9 gradually decreased from 1 to 32 weeks of age. The protein expressions of COL10A1 and Runx2 were maintained at a high level at 4-12 weeks of age. After static mechanical pressure loading, the damage and reduction in the bone mineral density (BMD) in the12-week-old group was greater than those in the 32-week-old group.An inconsistency between the condyle and articular disc during growth and development may be a causal factor for temporomandibular disorders TMDs in adolescents. Our findings suggest that the response of the adult condyle to the mechanical pressure is significantly greater than that of the adolescent condyle; however, with regard to reconstruction, the situation is reversed, which may influence the pathological progress of TMDs.

In addition to understanding the various meanings attached to the word “pressure” one also has to comprehend the meanings of the phrases in which the term “pressure” appears. For instance one comes across the following combinations: “static-fluid pressure”, “thermodynamic pressure”, “mechanical pressure”, “contact pressure”, “stagnation pressure”, “vapor pressure”, “electro-osmotic pressure”, etc., One also often comes across the comment that “pressure is the Lagrange multiplier that enforces the constraint of incompressibility” and that “pressure is the mean normal stress”. In general the word “pressure” with different significations, is used with gay abandon without paying proper attention to its usage 1 . The distinction in the meanings of the above terms assumes paramount significance when discussing properties of materials, which could possibly depend on “pressure”. In this short note we discuss the distinction between various significations of the word “pressure”, and their implications with regard to response relations for bodies.

This paper provides an overview of Spark Plasma Sintering (SPS), which is an advanced technology for high-speed sintering of powder materials by applying mechanical pressure to the powder compact and heating it using a pulsed direct current. Some examples of the successful application of the SPS technology in producing materials with high strength characteristics are shown. By optimizing the SPS regimes, the hardness of pure WC ceramics Hv=30÷31 GPa (20% higher than that of conventional materials), hardness of pure Al2O3 ceramics Hv=23.5 GPa (50% higher than that of conventional materials) and limit strength of the heavy alloy W–Ni–Fe σT=2500 MPa (2 times higher than that of conventional materials) are achievable.

Two alumina pipes were joined with an alumina–20 mass% zirconia composite insert for 4 and 8 h at 1650 °C and 1700 °C under a low mechanical pressure of 0.05 MPa. Although plate-like voids were observed along the interfaces in the specimens joined at 1650 °C, such voids were replaced with smaller round pores in specimens bonded at 1700 °C owing to local plastic deformation of the insert at the joint interfaces. In addition, the zirconia grains of the insert were deeply incorporated into alumina grains in the parent alumina at the interfaces at 1700 °C. Because of these microstructural effects, the specimens joined at 1700 °C showed relatively high flexural strengths both at room temperature and at 1200 °C that were close to that of the parent alumina, and most of the specimens were fractured from the parent alumina.

The current study focuses on the recovery of grape seed oil by supercritical CO2 extraction. Grape seeds from six grape cultivars were extracted in two subsequent harvesting years, and the resulting oils were characterized for the relative amount of: (a) lipid classes; (b) lipid acyl chains; and (c) tocopherols and tocotrienols. Comparative extractions were performed by utilizing n-hexane as solvent and by mechanical pressure. A well-established modeling approach was applied to evaluate the mass transfer parameters affecting the kinetics of supercritical CO2 extraction: with these parameters, process scale-up can be addressed. The results reported in this study testify the potentiality of grape seed oil as a source of unsaturated fatty acids and tocols. Moreover, they offer a clear picture of the similarities and differences among oils from different grape cultivars and obtained through different extraction techniques.

Inkjet-printed Ag grids were combined with graphene films synthesized using a chemical vapor deposition method to form highly flexible transparent electrodes with low resistances. Morphological characteristics, sheet resistances, transmittances, and bending test results are reported. A synergetic effect due to the mechanical pressure from graphene films on Ag grids was discovered and analyzed. Furthermore, polymer solar cells were fabricated with the developed electrodes and 2.9% maximum efficiency was obtained.

A major application of energy-harvesting technology is to power portable and wearable consumer electronics. We report a packaged power-generating insole with built-in flexible multi-layered triboelectric nanogenerators that enable harvesting mechanical pressure during normal walking. Using the insole as a direct power source, we develop a fully packaged self-lighting shoe that has broad applications for display and entertainment purposes. Furthermore, a prototype of a wearable charging gadget is introduced for charging portable consumer electronics, such as cellphones. This work presents a successful initial attempt in applying energy-harvesting technology for self-powered electronics in our daily life, which will have broad impact on people's living style in the near future.

A combination of combustion synthesis (CS) and spark plasma sintering (SPS) technology was employed in the fabrication of Al/AlN/CuAl 2 dense composites. Al/AlN/CuAl 2 composite powders in which a portion of the AlN was present in macro- and nanofiber forms were prepared by combustion of Al–Cu–5 wt.% (C 2 F 4 ) n , under a nitrogen atmosphere. The resulting composite powders were then subjected to consolidation by SPS at a dwell temperature level of 1500 °C, mechanical pressure of 60 MPa, and a non-isothermal heating time of 10 min. It is found that the actual thermal conductivity of Al/AlN/CuAl 2 composites fabricated with 5 wt.% (C 2 F 4 ) n is much higher than that of materials prepared in the absence (C 2 F 4 ) n . Maximum thermal conductivity (320 W/m K) was recorded for the samples prepared from an 0.8Al–0.2Cu–5 wt.% (C 2 F 4 ) n mixture. The influence of (C 2 F 4 ) n on the growth mechanism of AlN fibers and thermal conductivity of composite samples is discussed in light of the experimental data.

In the present work, our attention has been focused on the desired prevention of irreversible sulphation of negative test electrodes during cycling under simulated high-rate HEV duty. To this end, the negative active material was doped with carbon and, for comparison, with titanium dioxide as a nonconducting powdered additive, and the negative as well as positive electrodes were subjected to a defined pressure. Accelerated cycling revealed that electrodes doped with carbon in laboratory VRLA cells perform, in the first run, better than those doped with TiO 2 since they reached about 30,000 cycles regardless of the applied pressure. However, the electrode performances were almost equalized in the second run. Mechanical pressure of 4 N cm −2 has a pronounced favourable effect on the cycle life of negative electrodes with expanders. Higher pressures are not recommended. Electrodes doped with carbon but without standard expanders are capable of long-life cycling at elevated pressures around 6 N cm −2 . Their cycle life is comparable to that of the electrodes with expanders.

Cet article presente les aspects essentiels des tests neuro- dynamiques. Comment se definit un test positif, un test negatif, un faux positif ou un faux negatif, la mecanosensibilite, la differenciation structurelle, un test neurodynamique normal ou anormal ? Pour le clinicien, l’essentiel est de bien comprendre les points cles de ces tests afin de faire des diagnostics et des interpretations de tests neurodynamiques aussi precis que possible et etroitement integres a la recherche fondamentale et clinique. Cet article amene a la troisieme partie ou sont presentees certaines categories diagnostiques et leurs traitements. Niveau de preuve : non adapte

Dense 8YSZ was subjected to pulsed current activated sintering (PCAS) within 1 min of 8YSZ nanopowder preparation using a co-precipitation method. Sintering was accomplished by combining a pulsed current and mechanical pressure. Highly dense 8YSZ with a relative density of up to 99% was produced under simultaneous application of a pressure of 80 MPa and the pulsed current. The effects of the addition of Al 2 O 3 on the sintering behavior, mechanical properties, and ionic conductivities of 8YSZ were investigated.

Dense nanostructured WSi2–SiC composite was synthesized by pulsed current activated combustion synthesis method within 2 min in one step from mechanically activated powders of WC and 3Si. Simultaneous combustion synthesis and consolidation were accomplished under the combined effects of a pulsed current and mechanical pressure. Highly dense WSi2–SiC with relative density of up to 99.8% was produced under simultaneous application of a 80 MPa pressure and the pulsed current. The average grain size and mechanical properties of the composite were investigated.

Summary This article focuses on the prevention of tourniquet paralysis that may arise as a result of use of modern pneumatic tourniquets. Tourniquet paralysis is an injury caused by pneumatic tourniquet resulting from mechanical pressure on the nerves and anoxia. The injury can range from paraesthesia to complete paralysis. The motor functions are usually affected with sparing of sensation. High risk groups for tourniquet paralysis include older patients, hypertensive, obese patients and those with atherosclerosis. Adequate knowledge of the complications that can occur while using tourniquets is important to enable nurses to prevent and detect them early.

A powder processing technique is here presented. The process consists in a single short impulse (5–40 ms) of electric current (with current densities greater than 10 8 A/m 2 ) combined with mechanical pressure and allows for nearly complete to complete densification of powders (>90% of theoretical density) with energy inputs from 1 to 4.5 kJ/g. The fundamental process parameter known as SEI is analyzed and is correlated with other known electro-discharge sintering techniques which present analogous values. An experimental equation correlating SEI and densities is proposed. Theoretical physical considerations on the amplification of mechanical and electrical energies during the process are made to explain the sintering process and the experimental evidence.

A dense nanostructured 5TaSi 2 –SiC–Si 3 N 4 composite was synthesized by the high-frequency induction-heated combustion synthesis (HFIHCS) method within 1 min in one step from mechanically activated powders of 4TaN, TaC and 14Si. Simultaneous combustion synthesis and densification were accomplished under the combined effects of the induced current and mechanical pressure. A highly dense 5TaSi 2 –SiC–Si 3 N 4 composite with relative density of up to 96% was produced under the simultaneous application of a pressure of 60 MPa and the induced current. The average grain size and mechanical properties (hardness and fracture toughness) of the composite were investigated.

Boron carbide ceramics were obtained in 2 min by a method based on self-propagating high-temperature synthesis plus quick pressing (SHS/QP). The samples were densified to 98% of theoretical density under a large mechanical pressure (120 MPa) and a fast heating rate (2300 °C/min). The microstructure and mechanical properties were studied. The sample obtained at this heating rate presents an average grain size of 3 μm and a hardness of 34 ± 0.2 GPa.

Dense nanostructured 4ZrSi2–Si3N4 composite was synthesized by high frequency induction heated combustion synthesis (HFIHCS) method within 1 min in one-step from mechanically activated powders of 4ZrN and 11Si. Simultaneous combustion synthesis and consolidation were accomplished under the combined effects of an induced current and mechanical pressure. Highly dense 4ZrSi2–Si3N4 with relative density of up to 98% was produced under simultaneous application of a 60 MPa pressure and the induced current. The average grain size and mechanical properties of the composite were investigated.

Dense Ce0.8Gd0.2O2−δ was sintered by pulsed current activated sintering (PCAS) within 6 min from Ce0.8Gd0.2O2−δ nanopowder prepared by co-precipitation method. Sintering was accomplished under the combined effects of a pulsed current and mechanical pressure. Highly dense Ce0.8Gd0.2O2−δ with relative density of up to 96.3% was produced under simultaneous application of an 80-MPa pressure and the pulsed current. The effects of Fe2O3 additions on the sintering behavior, ionic conductivities, and mechanical properties of the Ce0.8Gd0.2O2−δ were investigated.

The simultaneous synthesis and densification of rhenium diboride is investigated starting from Re and B as reactants by using the Spark Plasma Sintering (SPS) apparatus. It is shown that SPS represents an effective technique to synthesize ReB 2 bulk samples with high purity and density. In particular, a dense product with traces of secondary phases (Re 7 B 3 ) is obtained in 35 min of total processing time by applying a maximum temperature of 1600 °C and a mechanical pressure of 20 MPa.

Dense nanophase 8 mol% yttria-stabilized zirconia was sintered by high-frequency induction heated sintering (HFIHS) within 6 min from 8YSZ nanopowder prepared by co-precipitation method. Sintering was accomplished under the combined effects of an induced current and mechanical pressure. Highly dense 8YSZ with relative density of up to 96% was produced under simultaneous application of a 60-MPa pressure and the induced current. The effects of Fe 2 O 3 additions on the sintering behavior, mechanical properties and ionic conductivities of the 8YSZ were investigated.

Dense nanostructured TiSi 2 –SiC composite was synthesized by high-frequency-induced heated combustion synthesis method within 1 min in one step from TiC and 3Si powders. Simultaneous combustion synthesis and densification were accomplished under the combined effects of an induced current and mechanical pressure. Highly dense TiSi 2 –SiC with relative density of up to 99% was produced under the simultaneous application of a 60 MPa pressure and the induced current. The mechanical properties of the composite were investigated.

The critical current density, J c , in applied magnetic field, B , of MgB 2 tape fabricated by a powder-in-tube (PIT) method via ex - situ process was dramatically improved by using MgB 2 powder made from MgH 2 and amorphous boron. The starting powder was obtained from the core of an MgB 2 tape prepared via an in - situ process of PIT method. The highest J c at 10 T and 4.2 K (4.5 × 10 3 A/cm 2 ) exceeds not only that of conventional ex - situ processed MgB 2 tape made from commercial MgB 2 powder ( 2 ), but also that of in - situ processed tape (3.4 × 10 3 A/cm 2 ). This drastic improvement in J c – B property of ex - situ MgB 2 tape is considered to be due to the enhancement in the B irr of MgB 2 core. On the other hand, we also found that the slope of J c – B line was different between ex - situ MgB 2 tape and in - situ processed tape, and it resulted in the higher J c of ex - situ processed tape than that of in - situ processed tape. This difference is considered to originate in the difference of the effective pinning mechanism between in - situ processed and ex - situ processed tapes, and the J c – B property of ex - situ processed tape is affected by the introduction of extra lattice distortion via mechanical pressure of PIT process.

A vast literature on electromagnetic and mechanical bioeffects at the bone and soft tissue level, as well as at the cellular level (osteoblasts, osteoclasts, keratinocytes, fibroblasts, chondrocytes, nerve cells, endothelial and muscle cells) has been reviewed and analysed in order to show the evident connections between both types of physical energies. Moreover, an intimate link between the two is suggested by transduction phenomena (electromagnetic-acoustic transduction and its reverse) occurring in living matter, as a sound biophysical literature has demonstrated. However, electromagnetic and mechanical signals are not always interchangeable, depending on their respective intensity. Calculations are reported in order to show in which cases (read: for which values of electric field in V/m and of mechanical pressure in Pa) a given electromagnetic or mechanical bioeffect is only due to the directly impinging energy or even to the indirect transductional energy. The relevance of the treated item for the applications of medical physics to regenerative medicine is stressed.

Dense MoSi 2 –SiC composite was synthesized by high-frequency induction heated combustion synthesis method within 2 min in one step from elemental powders of Mo, Si and C. Simultaneous combustion synthesis and densification were carried out under the combined effect of an induced current and mechanical pressure. Highly dense MoSi 2 –SiC with relative density of up to 98% was produced under simultaneous application of a 60 MPa pressure and the induced current. The average grain size of MoSi 2 and SiC were about 3.5 and 1.5 μm, respectively. And minor amount of Mo 5 Si 3 C was present. The fracture toughness and hardness values obtained were 4.8 MPa m 1/2 and 1410 kg/mm 2 , respectively.

Since 1983, it has been claimed that pressure applied on a lead-acid battery increases its cycle life. But until now, the use of pressure in production batteries was limited by the mechanical properties of the conventional separation systems (absorptive glass mat (AGM), and gel) which cannot withstand mechanical pressure. In 1997, Daramic developed the new acid jellying separator (AJS) with the aim of combining the advantages of both conventional separation systems and to allow the application of lasting plate group pressure. The new separation system was evaluated and much information was gained on the effect of pressure in a lead-acid battery, e.g. on the evolution of the mechanical pressure during one cycle and during cycle life.

We propose an organic solvent method to recover silicon cells from conventional crystalline silicon PV modules. From dissolution tests of EVA by various kinds of organic solvents, it was found that trichloroethylene could dissolve cross-linked EVA sample kept at 80°C. Applying this method to “one cell” module (125×125 mm), it was found that mechanical pressure is important to suppress swelling of the EVA. After immersing the module in trichloroethylene at 80°C for 10 days, we have successfully recovered the silicon cell without any damage.

Cycling experiments showed that the behavior of compressed test cells is more reproducible with the new separators (Amer-Sil and Daramic) than with the AGM separators used in our previous work; internal shorts did not appear. Optimum mechanical pressure was found to be close to 4 N/cm 2 , at which the cycle life of positive test electrodes exceeded 600 cycles and that of the negatives was more than 800 cycles, both at 100% DOD. Measurements of pressure changes in test cells with lead sheet counter electrodes showed that the volume changes of positive test electrodes follow the expected course, i.e. expansion on discharge and vice versa. The volume increase of the negatives, which may be attributed to the expander, can be prevented or even overcompensated by the applied mechanical pressure.

Choroidal osteoma is a rare, yellowish-white lesion of the choroid that predominantly affects young women in the second decade of life. Subretinal neovascularization or collection of subretinal fluid may occur in 50 % or more patients in the long run. A 15-year-old girl presented to our practice with bilateral choroidal osteoma associated with advanced bilateral optic atrophy. The underlying cause for optic atrophy is unclear; possible explanations include mechanical pressure effect and ischemic damage.

A nanopowder of FeAl was synthesized from Fe and Al powders by high-energy ball milling. A dense nanostuctured FeAl was consolidated by high frequency induction heated sintering method within 2 min from mechanically synthesized powders of FeAl and horizontally milled powders of Fe + Al. The consolidation was accomplished under the combined effects of an induced current and mechanical pressure. The grain size, sintering behavior and hardness of FeAl sintered from horizontally milled Fe + Al powders and high-energy ball milled FeAl powder were compared.

The alteration and weathering of stone is basically determined by natural and anthropogenic impacts influencing various physical, chemical and biological damage factors at the object site. Whether as direct or catalytically enhancing factor, the biodeterioration of stone is coupled with nearly all environmentally induced degradation processes: the presence of the one makes deterioration by the other all the more effective. The bioreceptivity of stone is described by its structure and chemical composition, while the intensity of the microbial contamination is determined by the referring climatic conditions and the anthropogenic euthrophication of the atmosphere. The microflora improves the nutrient and moisture-restricted growth conditions on building stones by the formation of surface-covering biofilms. Besides the aesthetical impairment caused by the coloured biopatina, the biofouling effect promotes even “abiotic” deterioration processes due to the alteration of the material structure as well as their thermo-hygric properties; in addition, mechanical pressure due to the shrinking and swelling of the colloidal biofilms might cause a further weakening of the mineral lattice. Acidolytic and oxido-reductive biocorrosion processes complete the biodeteriorating attack of stone acting as a preliminary precursor for the latter formation of detrimental crusts. Suitable and reliable methods for the detection of biodeterioration processes are available, but only the interdisciplinary diagnosis and evaluation of the entire decay process of stone allows the formulation of adaequate countermeasure strategies. In case the significance of biodeterioration impacts is proven, the possible effects of the microbial contamination on cleaning procedures, protective treatments as well as biocidal applications has to be considered. This paper will give a comprehensive overview to the biodeterioration of stone and stresses the practical relevance for the conservation.

Summary The induction of haustoria formation in Cuscuta reflexa proved to be independent of the presence of a suitable potential host. The induction, caused by mechanical pressure, was also possible in non-twining stems of the isolated parasite without applying any exogenous hormones. Over a period of time it was possible to induce haustoria mechanically repeatedly on the isolated Cuscuta stems. Haustoria formation was restricted to a subapical region of the parasite’s stem, which is the area where the most intensive elongation of the Cuscuta stem takes place. During haustorial development, the growth rate of the parasite is retarded. An interaction of IAA and cytokinine, possibly involved in the regulation of these processes, is discussed.

In the present paper the formation of high strength structures of WC–Co and W–Ni–Fe–Co composite materials is investigated and optimal operating parameters are defined. Tungsten carbide–cobalt and W–Ni–Fe–Co composites were produced by the method of high-voltage electrical discharge together with application of mechanical pressure to powder compact. It was found that the density and hardness of composite material reach its maximum values at certain magnitudes of applied pressure and high-voltage electrical discharge parameters. We show that there is an upper level for the discharge voltage and applied pressure beyond which the powder of composite material disintegrates like an exploding wire. We have invented a mathematical model of powder material behavior in volumetric energy emission which is based on the laws of conservation of mass, impulse and energy together with electrodynamics equations. Equations of state of powder materials have been used with account of experimental results obtained. Our analysis has been carried out from the modern viewpoints of thermodynamics of irreversible processes in open systems. Due to our results it is possible to determine optimal parameters for electro-discharge compaction of WC–Co and W–Ni–Fe–Co powder materials with preset properties.

Laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) has been used to investigate the elemental variation for tree rings of 20-year-old clonal Norway spruce trees that grew nearby an aluminum smelter. Four years prior to analysis this source of fluoride pollution was shut down and the subsequent variation of the concentration of elements in the tree ring according to their mobility in the tree stem was investigated by means of a LA-ICPMS. The elements Al, Fe, Ca, Ba and Sr showed a significant increase in values after the pollution shutdown. Elements with similar chemical behavior and mobility show similar patterns of distribution. Circular investigations of tree rings show a variation of up to 60% of the elemental concentration depending on the geographical direction following the changing properties (e.g density) of wood. The circular pattern correlate again for elements with similar properties and function. Furthermore, wood which develops in response to unbalanced mechanical pressure, such as wind for example (so called compression wood) shows significant differences in element concentration compared with unstressed wood.

CLINICAL CHALLENGE Demonstration of lepra bacilli on skin slit and scrape smears stained by the Ziehl-Neelsen method is an important diagnostic aid for leprosy, especially in resource-poor settings. The technique involves pinching the fold of skindusually of the earlobedtightly between the thumb and index finger until it blanches, making a 5-mm long and 2-mm deep cut, scraping the base of the cut after turning the blade by 908 to collect (bloodless) fluid, and making a smear followed by staining. Often, the physician’s ability to maintain sufficient mechanical pressure to cause blanching is inadequate and may result in a bloody smear causing discomfort to the patient because of multiple slits.

Mechanical pressure is shown to have a large effect on lithium plating morphology, lithium cyclability and the propensity to form dendritic shunts. In situ examination of lithium growth during cycling was carried out using a special force-displacement instrumented apparatus. Lithium growth is found to strongly depend on electrode stack pressure. The build up of electrode stack pressure in constant volume cells is examined in terms of cell design, component thickness and component compressibility. Methods of obtaining optimum lithium cyclability in a constant volume cell with respect to electrode stack pressure are discussed and illustrated.

The analgesic drug butorphanol tartrate has proved useful clinically in horses and dogs but its analgesic profile had not yet been investigated in sheep. This study was initiated to determine the thermal and mechanical antinociceptive activity of butorphanol (at the dose rates 0.05, 0.1 and 0.2 mg kg-1) in sheep. The drug produced significant analgesia in the thermal test system, the duration of which was dose related but no significant elevation in mechanical pressure thresholds could be detected. In a further set of experiments the dose rate was increased to 0.4 mg kg-1 and mechanical testing was repeated. There was still no clinically significant elevation in pressure thresholds. At a dose rate of 0.2 mg kg-1 the drug had no detectable effect on respiratory blood gas tensions. Behavioural changes were severe if a dose rate of 0.2 mg kg-1 was exceeded.

Summary Genes ar and n both appear to influence seed weight in peas via the maternal tissue but appear to do this in quite distinct ways. Gene n only decreases seed weight late in seed development probably by restricting the inflation of the seed due to the limited size of the pod lumen. This mechanical pressure also appears to lead to late abortion of developing seeds. Gene ar influences seed weight from the start of development probably by reducing assimilate movement into the seed due to the small size of the hilum and funiculus. The results of reciprocal crosses indicate that in plants prossessing genes ar and n the maternal genotype determines seed weight. Normally this appears to be due to an interaction between the maternal and embryo genotypes. These results suggest that genes ar and n may be of use in studies of the source-sink relationship between the maternal plant and the developing seed.