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The mechanisms behind the cardiovascular and renal benefits of empagliflozin is not fully understood. The positive impact of the medication on cardiovascular mortality can not be solely attributed to its antidiabetic effect, with a metabolic mechanism possibly involved. To investigate the metabolic effects of empagliflozin treatment (10 mg/kg/day for 6 weeks), we used an adult male rat model with serious vascular complications associated with metabolic syndrome and prediabetes. Impaired glucose tolerance, severe albuminuria and impaired insulin sensitivity were induced by intragastric administration of methylglyoxal and high sucrose diet feeding for four months. Although empagliflozin decreased body weight, non-fasting glucose and insulin, glucagon levels remained unchanged. In addition, empagliflozin increased adiponectin levels (+40%; p < 0.01) and improved skeletal muscle insulin sensitivity. Increased non-esterified fatty acids (NEFA) in empagliflozin-treated rats is understood to generate ketone bodies. Empagliflozin increased β-hydroxybutyrate levels in serum (+66%; p < 0.05) and the myocardium (30%; p < 0.01), suggesting its possible involvement as an alternative substrate for metabolism. Empagliflozin switched substrate utilisation in the myocardium, diverting glucose oxidation to fatty acid oxidation. Representing another favorable effect, empagliflozin also contributed to decreased uric acid plasma levels (--19%; p < 0.05). In the kidney cortex, empagliflozin improved oxidative and dicarbonyl stress parameters and increased gene expression of β-hydroxybutyrate dehydrogenase, an enzyme involved in ketone body utilisation. In addition, empagliflozin decreased microalbuminuria (--27%; p < 0.01) and urinary neutrophil gelatinase-associated lipocalin (NGAL) excretion (--29%; p < 0.01). Our results reveal the important systemic metabolic effect of empagliflozin on alterations in substrate utilisation and on increased ketone body use in prediabetic rats. Improved oxidative and dicarbonyl stress and decreased uric acid are also possibly involved in the cardio- and reno-protective effects of empagliflozin. [ABSTRACT FROM AUTHOR]

The shock response of a polymer-bonded copper powder was investigated by means of plate impact experiments in a gas gun (pressure range 1–8 GPa) and using in-contact explosive loading (pressures up to 37 GPa). Stress gauges were used to determine the material shock states in the planar impact, and the experimental data of shock and particle velocities (U, u) were fitted to a straight line giving a Hugoniot equation of state U = (0.85 ± 0.08) + (2.64 ± 0.05) u . In the explosive loading experiments, the shock speed in the material was measured using optical methods, and impedance matching was performed to determine the shock state in the sample. Comparison between the two experiments shows that the states attained in the lower-pressure range (planar impact experiments) and higher-pressure range (explosive loading) follow the same Hugoniot curve, within 4% deviation. [ABSTRACT FROM AUTHOR]

Two new carbon chain radicals terminated with a nitrile group, C[sub 4]N and C[sub 6]N, have been detected in a supersonic molecular beam by Fourier transform microwave spectroscopy. In addition, at least three hyperfine-split rotational transitions of the singly-substituted isotopic species of C[sub 3]N have also been observed. Both C[sub 4]N and C[sub 6]N are linear chains with ²Π electronic ground states, and both radicals have resolvable hyperfine structure and lambda-type doubling in their lowest rotational levels. At least four transitions in the lowest-energy fine structure component (²Π[sub ½]) were measured between 7 and 22 GHz for both molecules, and at most nine spectroscopic constants were required to reproduce the measured spectra to a few parts in 10[sup 7]. Precise sets of rotational, centrifugal distortion, spin-rotation, and hyperfine coupling constants were also determined for the isotopic species of C[sub 3]N by combining the centimeter-wave measurements here with previous millimeter-wave data. The [sup 13]C hyperfine coupling constants of isotopic C[sub 3]N differ from those of the isoelectronic chain C[sub 4]H, but are fairly close to those of isovalent C[sub 2]H, indicating a nearly pure ²Σ electronic ground state for C[sub 3]N. Although the strongest lines of C[sub 6]N are more than five times less intense than those of C[sub 5]N, owing to large differences in the ground state dipole moments, both new chains are more abundant than C[sub 5]N. Searches for C[sub 7]N have so far been unsuccessful. The absence of lines at the predicted frequencies implies that the product of the dipole moment times the abundance (µ·N[sub a]) is more than 60 times smaller for CTN than for C[sub 5]N, suggesting that the ground state of C[sub 7]N may be ²Π, for which the dipole moment is calculated to be small. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is a key indicator of soil health as it is important in essential soil functions related to nutrient cycling and soil productivity. Although, it can take several decades to increase SOC in semi-arid ecoregions, it is possible that the low organic matter background in sandy soils typical of semi-arid soils may show greater fluctuations compared to soils from other regions. This study was conducted to evaluate the temporal C and N dynamics of cotton (Gossypium hirsutum L.) cropping systems in a semi-arid region. The effects of no-tillage (NT) and cover crop use on SOC, potassium permanganate oxidizable carbon (POXC), inorganic nitrogen (Ninorg), and microbial respiration were investigated in a long-term study (~19 yr) at Lamesa, TX, comparing conventional tillage (CT), winter fallow, to no-tillage rye cover (R-NT), and no-tillage mixed species cover (M-NT) on an Amarillo fine sandy loam. Results showed SOC and POXC were greatest during periods of active cover crop and cotton root growth. Soil organic C and POXC were significantly correlated (R2 = 0.75; p < 0.0001), but poorly correlated to microbial respiration (R2 = 0.41, p = 0.0001; and R2 = 0.02, p = 0.8781, respectively). Conservation management practices did not impact Ninorg. Soil organic C and POXC levels were more variable than previously reported and responded to active root growth in this semi-arid, sandy soil. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Cardiac tissue deformation can modify tissue resistance, membrane capacitance and ion currents and hence cause arrhythmogenic slow conduction. Our aim was to investigate whether uniaxial strain causes different changes in conduction velocity (θ) when the principal strain axis is parallel vs perpendicular to impulse propagation. Methods: Cardiomyocyte strands were cultured on stretchable custom microelectrode arrays, and θ was determined during steady‐state pacing. Uniaxial strain (5%) with principal axis parallel (orthodromic) or perpendicular (paradromic) to propagation was applied for 1 minute and controlled by imaging a grid of markers. The results were analysed in terms of cable theory. Results: Both types of strain induced immediate changes of θ upon application and release. In material coordinates, orthodromic strain decreased θ significantly more (P < .001) than paradromic strain (2.2 ± 0.5% vs 1.0 ± 0.2% in n = 8 mouse cardiomyocyte cultures, 2.3 ± 0.4% vs 0.9 ± 0.5% in n = 4 rat cardiomyocyte cultures, respectively). The larger effect of orthodromic strain can be explained by the increase in axial myoplasmic resistance, which is not altered by paradromic strain. Thus, changes in tissue resistance substantially contributed to the changes of θ during strain, in addition to other influences (eg stretch‐activated channels). Besides these immediate effects, the application of strain also consistently initiated a slow progressive decrease in θ and a slow recovery of θ upon release. Conclusion: Changes in cardiac conduction velocity caused by acute stretch do not only depend on the magnitude of strain but also on its orientation relative to impulse propagation. This dependence is due to different effects on tissue resistance. [ABSTRACT FROM AUTHOR]

Expansion of apple growing to dry areas requires reliable approaches to select genotypes tolerant to water stress. We have simulated apple tree transpiration (Ec) from different commercial orchards and compared it with actual transpiration (Ea) derived from sap flow measurements. The modelling approach lies in rearranging a parameterized P-M Equation and incorporating in it a stomatal conductance model derived from meteorological variations. The model uses diurnal courses of variables instead of commonly used daily means. We then wrote a complex P-M Equation which already includes the canopy conductance as the function of radiation and vapour pressure deficit. For model calibration, an extensive experimental dataset of tree transpiration was collected from 2011 to 2013 in various sites of Albania and Kosovo, ranging from very warm to temperate. The daily pattern of canopy conductance for water vapour at canopy level provided by the model offers an unprecedented insight into rapid response to humidity of different cultivars as well as their light saturation levels. The satisfactory performance of this functional model should improve the precision of current empirical approaches followed to compute fruit tree water requirements and can be a promising tool for early and quick evaluation of water stress tolerance in apple genotypes. [ABSTRACT FROM AUTHOR]

The article offers information on several national and regional bryophytes. It says that the Bryoerythrophyllum inaequifolium species of pantropical montane weakly penetrates to North Carolina's warm temperate zone in south-eastern North America. It states that Bryum canariense prefers to grow in Mediterranean areas and adjacent coastal areas. It adds that the species of Chionoloma bombayense have the greatest number in Asia.

Sorghum (Sorghum bicolor L. Moench) has high water use efficiency, and is therefore widely cultivated in the Southern High Plains (SHP). Interest in sorghums for biofuel feedstock has increased recently as ethanol demand expands. Unlike grain sorghum, little data are available on N fertilizer requirements for ethanol production from sweet or forage sorghum production. Our objective was to compare ethanol yields and determine optimal N fertilizer needs for ethanol production from sweet sorghum and photoperiod sensitive (PPS) sorghum with limited irrigation in the SHP. Nitrogen fertilizer rates from 0 to 168 N kg ha-1 were tested on four sorghum cultivars (two sweet and two PPS) on Acuff sandy clay loam near Lubbock, TX in 2008 and 2009. Total dry matter (TDM) yields averaged 13Mg ha-1 across years, cultivars, and N rates. Nitrogen fertilizer response in TDM was observed only in 2009, but bagasse yields responded to N fertilizer in both years. Cellulosic ethanol yields were greater with PPS sorghums than with sweet sorghums in both years. However, total ethanol yields were greater with sweet sorghums than PPS sorghums. Cellulosic ethanol and total ethanol yields responded to N in 2009 only. High preplant soil NO3 in 2008 apparently precluded TDM and ethanol yield response to N fertilizer. The optimum agronomic N fertilizer rate for ethanol and TDM across all four sorghums was 108 kg ha-1 respectively in 2009. The optimum N fertilizer rate for maximum profit with $0.70 kg N-1 and $0.50 L-1 ethanol was 101 kg ha-1. [ABSTRACT FROM AUTHOR]

Proper development of the nervous system requires that a carefully controlled balance be maintained between both proliferation and neuronal survival. The process of programmed cell death is believed to play a key role in regulating levels of neuronal survival, in large part through the action of antiapoptotic proteins, such as Bcl-2. Consistent with this, Bcl-2 has been shown to be a key regulator of apoptotic signaling in post-mitotic neurons. However, we still know remarkably little regarding the role that Bcl-2 plays in regulating the survival of specific motor neuron populations. In the present study, we have examined somatic motor neurons of the lumbar spinal cord, and branchiomotor neurons of the facial nucleus in bcl-2-null mice to determine the differential dependence among motor neuron populations with respect to Bcl-2-mediated survival. Examination of neuronal and axon number, axonal area, and the distribution of axonal loss in bcl-2-null mice demonstrates that, in contrast to the great majority of alpha motor neurons, gamma motor neurons exhibit a unique dependence upon bcl-2 for survival. These results demonstrate, for the first time, the connection between Bcl-2 expression, motor neuron survival, and the establishment of different motor populations.Cell Death and Differentiation (2008) 15, 691–699; doi:10.1038/sj.cdd.4402294; published online 21 December 2007 [ABSTRACT FROM AUTHOR]

Among the most common non-conventional wastewater treatment techniques used in the Czech Republic are waste stabilisation ponds (WSP), subsurface horizontal flow constructed wetlands (CW) and vertical flow groundfilters (GF). These extensive systems can be advantageously used for treatment of waters coming from sewerages where the ballast weighting commonly makes more than half of dry-weather flow. The monitoring was focused at 14 different extensive systems. Organics removal efficiencies were favourable (CW-82%; GF-88%); in the case of WSP only 57% due to the algal bloom. Total nitrogen removal efficiencies were 43 and 47% for WSP and GF; in the case of CW only 32% due to often occurring anaerobic conditions in filter beds. Total phosphorus removal efficiencies were 37, 35 and 22% for WSP, GF and CW, respectively. Often occurring problems are the ice-blockage of surface aerators at WSP during wintertimes, the pond duckweed-cover or the algal bloom at WSP during summers; a gradual colmatage of filter systems; and the oxygen deficiency in beds of subsurface horizontal flow constructed wetlands. Czech legal regulations do not allow treated wastewater disposal into underground waters. There is only an exception for individual family houses. Up to now, knowledge gained by monitoring of a village (which uses the infiltration upon a permission issued according to earlier legal regulations) have not shown an unacceptable groundwater quality deterioration into the infiltration areas. [ABSTRACT FROM AUTHOR]

Studies the effect of neurotrophin-3 in noradrenergic neuron function and opiate withdrawal. Attenuation of somatic symptoms and aversion of opiate withdrawal in mice; Restoration of opiate withdrawal symptoms by transgene-derived NT-3; Modulation of opiate withdrawal and noradrenergic signalling.

A method for simultaneous determination of lead and thallium by photon activation analysis with radiochemical separation using irradiation with bremsstrahlung produced by a 20 MeV microtron is described. The detection limits for 500-mg samples of 0.9 μg·g-1 and 0.15 μg·g-1 for lead and thallium, respectively, were achieved that are sufficiently low for the reliable determination of both elements at levels commonly occurring in environmental samples and at elevated levels in biological materials. The accuracy of the procedure developed was proved by analyses of a number of environmental and biological reference materials. Possibilities of detection limit improvements are also discussed. [ABSTRACT FROM AUTHOR]

Long-time brittle failure limits the lifetime of polyethylenepipes for water and gas distribution. The same type of failure wasobserved in single-edge-notched tensile specimens under plane strainconditions. The crack opening displacement (COD) was measured as afunction of time and temperature, and the time to complete fracture( t f) was measured. An empirical failure time extrapolationrelation based on temperature was developed using the Arrheniusequation. The experimental and extrapolated data for80°C were found to correlate very well. Using thisrelation, structural parameters were characterised by the StepwiseIsothermal Segregation/Differential Scanning Calorimetry (SIS/DSC)method. The correlation between fracture and structural parameters wasfound. [ABSTRACT FROM AUTHOR]

Distributions of motor axons to different types of intrafusal fiber were reconstructed from serial 1-μm thick transverse sections of six poles of muscle spindle in the rat soleus. Motor axons innervated (dynamic) bag fibers, or (static) bag fibers in conjunction with chain fibers. However, approximately forty percent of axons that supplied the spindles synapsed on both bag and bag, or bag and chain fibers. The significance of this co-innervation of dynamic and static intrafusal fibers is discussed relative to the general organization and function of mammalian spindles. [ABSTRACT FROM AUTHOR]

The pattern of regional expression of a slow-tonic myosin heavy chain (MHC) isoform was studied in developing rat soleus intrafusal muscle fibers. Binding of the slow-tonic antibody (ATO) began at the equator of prenatal intrafusal fibers where sensory nerve endings are located, and spread into the polar regions of nuclear bag and bag fibers but not nuclear chain fibers during ontogeny. The onset of the ATO reactivity coincided with the appearance of equatorial clusters of myonuclei (nuclear bag formations) in bag and bag fibers. Moreover, the intensity of the ATO reaction was strongest in the region of equatorial myonuclei and decreased with increasing distance from the equator of bag and bag fibers at all stages of prenatal and postnatal development. The polar expansion of ATO reactivity continued throughout the postnatal development of bag fibers, but ceased shortly after birth in bag fiber coincident with innervation by motor axons. Thus, afferents that innervate the equator might induce the slow-tonic MHC isoform in bag and bag fibers by regulating the myosin gene expression by equatorial myonuclei, and efferents or twitch contractile activity might inhibit the spread of the slow-tonic MHC isoform into the poles of bag but not bag fibers. Absence of ATO binding in chain fibers suggests that chain myotubes may not be as susceptible to the effect of afferents as are myotubes that develop into bag and bag fibers. The different patterns of slow-tonic MHC expression in the three types of intrafusal fiber may therefore result from the interaction of three elements: sensory neurons, motor neurons, and intrafusal myotubes. [ABSTRACT FROM AUTHOR]

Whether nerve activity and active contraction of myotubes are essential for the assembly and initial differentiation of muscle spindles was investigated by paralyzing fetal rats with tetrodotoxin (TTX) from embryonic day 16 (E16) to E21, prior to and during the period when spindles typically form. TTX-treated soleus muscles were examined by light and electron microscopy for the presence of spindles and expression of myosin heavy chain (MHC) isoforms by the intrafusal fibers. Treatment with TTX did not inhibit the formation of a spindle capsule or the expression of a slow-tonic MHC isoform characteristic of intrafusal fibers, but did retard development of spindles. Spindles of TTX-treated E21 muscles usually consisted of one intrafusal fiber (bag) only rather than two fibers (bag and bag) typically present in untreated (control) E21 spindles. Intrafusal fibers of TTX-treated spindles also had only one sensory region supplied by multiple afferents, and were devoid of motor innervation. These features are characteristic of spindles in normal E18-E19 muscles. Thus, nerve and/or muscle activity is not essential for the assembly of muscle spindles, formation of a spindle capsule, and transformation of undifferentiated myotubes into the intrafusal fibers containing spindle-specific myosin isoforms. However, activity may promote the maturation of intrafusal bundles, as well as the maturation of afferent and efferent nerve supplies to intrafusal fibers. [ABSTRACT FROM AUTHOR]

The expression of several isoforms of myosin heavy chain (MHC) by intrafusal and extrafusal fibers of the rat soleus muscle at different stages of development was compared by immunocytochemistry. The first intrafusal myotube to form, the bag fiber, expressed a slow-twitch MHC isoform identical to that expressed by the primary extrafusal myotubes. The second intrafusal myotube to form, the bag fiber, expressed a fast-twitch MHC similar to that initially expressed by the secondary extrafusal myotubes. At subsequent stages of development, the equatorial and juxtaequatorial regions of bag and bag intrafusal myofibers began to express a slow-tonic myosin isoform not expressed by extrafusal fibers, and ceased to express some of the MHC isoforms present initially. Myotubes which eventually matured into chain fibers expressed initially both the slow-twitch and fast-twitch MHC isoforms similar to some secondary extrafusal myotubes. In contrast, adult chain fibers expressed the fast-twitch MHC isoform only. Hence intrafusal myotubes initially expressed no unique MHCs, but rather expressed MHCs similar to those expressed by extrafusal myotubes at the same chronological stage of muscle development. These observations suggest that both intrafusal and extrafusal fibers develop from common pools of bipotential myotubes. Differences in MHC expression observed between intrafusal and extrafusal fibers of rat muscle might then result from a morphogenetic effect of afferent innervation on intrafusal myotubes. [ABSTRACT FROM AUTHOR]

The expression of four myosin heavy chain (MHC) isoforms, avian slow-tonic (ATO) or neonatal-twitch (ANT) and mammalian slow-twitch (MST) or fast-twitch (MFT) in intrafusal fibers was examined by immunocytochemistry of spindles in the tenuissimus muscle of adult eats. The predominant MHCs expressed by nuclear bag fibers were ATO and MST, whereas the MHCs prevalent in nuclear chain fibers were ANT and MFT. The expression of these isoforms of MHC was not uniform along the length of intrafusal fibers. In general, both bag and chain fibers expressed avian MHC in the intracapsular region and mammalian MHC in the extracapsular region. The nonuniform expression of MHCs observed along the length of bag and chain fibers implies that different genes are activated in myonuclei located in the intracapsular and extracapsular regions of the same muscle fiber. Regional differences in gene activation might result from a greater effect of afferents on myonuclei located near the equator of intrafusal fibers then on myonuclei outside the spindle capsule. [ABSTRACT FROM AUTHOR]

Features of the nerve supply and the encapsulated fibers of muscle spindles were assessed in grafted and normal extensor digitorum longus (EDL) muscles of rats by analysis of serial 10-μm frozen transverse sections stained for enzymes which delineated motor and sensory endings, oxidative capacity and muscle fiber type. The number of fibers was significantly more variable, and branched fibers were more frequently observed in regenerated spindles than in control spindles. Forty-eight percent of regenerated spindles received sensory innervation. Spindles reinnervated by afferents had a larger periaxial space than did spindles which were not reinnervated by afferents. Regenerated fibers innervated by afferents had small cross-sectional areas, equatorial regions with myofi-brils restricted to the periphery of fibers, unpredictable patterns of nonuniform and nonreversible staining along the length of the fiber for 'myofibrillar' adenosine triphosphatase (mATPase) after acid and alkaline preincubation. In contrast, regenerated fibers devoid of sensory innervation resembled extrafusal fibers in that they usually exhibited myofibrils throughout the length of the fiber, no central aggregations of myonuclei, uniform staining for mATPase and a reversal of staining for mATPase after preincubation in an acid or alkaline medium. Approximately thirty percent of encapsulated fibers devoid of sensory innervation stained analogous to a type I extrafusal fiber, a pattern of staining never observed in intrafusal fibers of normal spindles. Groups of encapsulated fibers all exhibiting this pattern of staining reflect that either these fibers may have been innervated by collaterals of skeletomotor axons that originally innervated type I extrafusal fibers or that fibers innervated by only fusimotor neurons express patterns of staining for mATPase similar to extrafusal fibers in the absence of sensory innervation. Sensory innervation may also influence the reestablishment, of multiple sites of motor endings on regenerated intrafusal fibers. Those regenerated fibers innervated by afferents had more motor endings than did regenerated fibers devoid of sensory innervation. Differences in size, morphology, and patterns of staining for mATPase and numbers of motor endings between fibers innervated by afferents and fibers devoid of sensory innervation reflect that afferents can influence the differentiation of muscle cells and the reestablishment of motor innervation other than during the late prenatal/early postnatal period when muscle spindles form and differentiate in rats. [ABSTRACT FROM AUTHOR]

Muscle spindles were either deafferented or deefferented by selectively severing the sensory or motor nerve supply to neonatal soleus muscles of rats at a time when spindles are formed but when intrafusal muscle fibers are structurally and immunocytochemically immature. Experimental muscles wereexcised two months after nerve section. Control and experimental spindles were examined using monoclonal antibodies specific for myosin heavy chains of slow-tonic (ALD58) and fast-twitch (MF30) chicken muscles. Only intrafusal fibers bound these antibodies in intact soleus muscles. The deefferented spindles exhibited a pattern of ALD58 and MF30 binding similar to that of normal adult intrafusal fibers, whereas deafferented intrafusal fibers were unreactive with the two antibodies. Thus intact sensory innervation is essential for myosin heavy chain expression in intrafusal muscle fibers during postnatal development of rat spindles. [ABSTRACT FROM AUTHOR]

Over 300 complete and incomplete cat muscle spindles were examined in serial transverse sections of tenuissimus muscles in search of spindles with more than two nuclear bag intrafusal muscle fibers. Several histochemical and histological stains were used to identify the intrafusal fibers and assess their motor and sensory innervation. About 13% of the spindles contained either three or four bag fibers rather than the usual two. Every multiple-bag-fiber spindle possessed at least one nuclear bag and one nuclear bag fiber. The supernumerary bag fibers were either another bag and/or bag fiber, or a mixed bag fiber. The extra bag fibers had the usual morphologic and histochemical properties of cat nuclear bag fibers. All multiple-bag spindles received primary sensory innervation, and most had secondary sensory endings in addition. Their motor pattern was similar in the number, appearance and disposition of intrafusal motor endings to that of the usual two-bag-fiber spindles. Bag fibers of the same kind shared motor nerve supply in three multiple-bag spindles in which tracings of individual motor axons were obtained histologically. It is unclear whether any functional advantage is conveyed to a muscle spindle by its having more than one bag and one bag fiber. [ABSTRACT FROM AUTHOR]

Over 150 complete and 139 incomplete single muscle spindles were examined in serial transverse sections of cat tenuissimus muscles in search for spindles lacking one of the two types of nuclear bag intrafusal fiber. Several histochemical reactions were used to type the intrafusal muscle fibers and assess the spindle motor and sensory innervation. One complete spindle lacked a bag fiber, and another spindle lacked a bag fiber. Several incomplete spindles also lacked bag fibers. In addition, ten double tandem spindles contained one capsular unit each that lacked the bag fiber, and one triple tandem spindle had two such capsules. All one-bag-fiber spindles had primary sensory innervation, but none had secondary sensory innervation. Their motor innervation was similar to that of the usual two-bag-fiber spindles in the number and disposition of intrafusal motor endings. It is unclear whether the one-bag fiber spindles, either single or tandem-linked, are products of an aberrant spindle development or represent a true anatomical and functional subcategory of the cat muscle spindle. [ABSTRACT FROM AUTHOR]

The sensory innervation of 46 poles of long chain intrafusal muscle fibers was studied histochemically by staining for NADH-TR in periodic, 8 μm thick transverse sections of cat muscle spindles. Each long chain fiber carried terminals of the primary sensory axon, and 23 of the fiber poles also displayed secondary sensory endings. With the NADH-TR reaction there was no apparent difference in the cross-sectional appearance of sensory endings on the long chain and on other nuclear chain fibers. However, the contact area between the secondary endings and the muscle fiber tended to be shorter on the long chain than on the neighboring chain fibers of shorter polar length. This was also the case for one long chain fiber in which the sensory innervation was examined in serial, 1 μm thick sections stained with toluidine blue. Discharges of the secondary sensory axons in cat spindles may be affected more by contraction of the shorter nuclear chain fibers than by activation of the long chain fibers. [ABSTRACT FROM AUTHOR]

Cat muscle spindles were studied histochemically in serial transverse sections of the tenuissimus muscle stained for myofibrillar ATPase, cholinesterase or NADH-tetrazolium reductase. The terminal sites of the primary and secondary sensory axons on intrafusal muscle fibers could be demonstrated due to their high NADH-TR activity. This sensory NADH-TR reactivity at the equator and in the juxtaequatorial regions disappeared following spindle chronic de-afferentation, but not after de-efferentation. Spindle poles that carried both primary and secondary sensory endings had a longer periaxial fluid space than poles with primary endings only, and their motor innervation, as determined by staining for ChE, was positioned at a greater distance from the equator. Some of the secondary endings occurred in intrafusal regions that displayed surface fiber ChE activity. The histochemical reaction for NADH-TR represents a simple, rapid and reliable method for studies of the distribution of sensory nerve terminals in the spindle. [ABSTRACT FROM AUTHOR]

Muscle spindles were studied histochemically in serial transverse sections of specimens of the cat tenuissimus muscle. The nuclear chain intrafusal muscles fibers were separated into three subtypes, called long, intermediate and typical. The long chain and intermediate chain fibers tended to assume a particular position within the axial bundle of intrafusal fibers. The fibers were usually located in that layer of chain fibers that was positioned farthest away from the bag fiber. Furthermore, they were usually situated adjacent to the bag fiber throughout much of the extent of the spindle pole. Some long chain and intermediate chain fibers had several fiber nuclei abreast at the equator rather than a single row of central nuclei, as in most nuclear chain fibers. The relative position of intrafusal fibers within the cat spindle may reflect their order of formation during development, with the fibers retaining, to a variable degree, their association with the bag fiber which acted as template. Thus, the axial position of long chain and intermediate chain fibers suggests that they are among the first nuclear chain fibers to form. This may play a role in the known preferential innervation of these chain fibers by skeleto-fusimotor axons. [ABSTRACT FROM AUTHOR]

Cat muscle spindles were examined histochemically in serial transverse sections of tenuissimus muscles stained for ATPase, NADH-TR and ChE alternating sequentially. Motor nerve terminals on nuclear bag, bag and nuclear chain intrafusal muscle fibers were identified in periodic sections stained for ChE. Intrafusal fiber regions that carried ChE-active areas were then examined in staining for NADH-TR. The motor endings on the three types of intrafusal fiber differed in their apparent histochemical content of both ChE and NADH-TR. The observations suggest that functional differences may exist among motor nerve terminals on the various intrafusal fiber types. [ABSTRACT FROM AUTHOR]

Cat tenuissmus muscles were deprived of motor nerve supply for three months by sectioning of the appropriate ventral spinal roots. Muscle spindles were located in the chronically de-efferented muscles and examined histochemically in serial transverse sections. Staining for nicotinamide adenine dinucleotide tetrazolium reductase showed that the spindle sensory innervation was preserved. The de-efferented intrafusal muscle fibers retained their differential staining with the reaction for myosin adenosine triphosphatase. However, all cholinesterase-active areas that are normally found along nuclear bag and nuclear chain intrafusal fibers demonstrated loss of the enzyme activity in the chronically de-efferented spindles. It is concluded that all histochemically demonstrable cholinesterase activity within the cat muscle spindle is dependent upon the continuous presence of motor innervation. [ABSTRACT FROM AUTHOR]

Muscle spindles were examined histochemically in serial transverse sections of cat tenuissimus muscles. The myofibrillar adenosine triphosphatase (ATPase) staining reaction was used to identify nuclear bag, bag and nuclear chain intrafusal muscle fibers. Regional differences in ATPase staining occurred along the bag and bag fibers but not along the chain fibers. All intrafusal fiber types displayed regional variability in staining for nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR). Motor nerve terminals were demonstrated along the poles of bag, bag and chain fibers by staining for cholinesterase (ChE). There was no consistent spatial correlation between the intensity of regional ATPase staining along the bag fibers and location, number or type of motor endings. However, most ChE deposits occurred in intrafusal fiber regions that displayed the greatest NADH-TR variability. Some fiber poles or whole intrafusal fibers were devoid of any ChE deposits but their ATPase and NADH-TR content was comparable to that of fibers bearing ChE deposits. The observations suggested that motor nerve fibers per se may not play a major role in determining the histoenzymatic content of intrafusal fibers. [ABSTRACT FROM AUTHOR]

A cat tenuissimus muscle spindle that contained two long chain intrafusal fibers in its distal pole is described. One of the fibers (1 c) had a histochemical profile (ATPase, NADH-TR, ChE reactions) of the kind which is characteristic for long chain fibers. The other fiber (1 c) consisted of two separate segments. The inner 1 c segment included the sensory equatorial region and was histochemically normal. The outer 1 c segment carried a motor plate, and did not stain for NADH-TR in the same way as the inner 1 c segment and the 1 c fiber. It is suggested that the unusual enzyme staining properties of the outer 1 c segment stemmed from its lack of sensory innervation, a situation which may have permitted the full expression of influences mediated by its motor nerve supply. [ABSTRACT FROM AUTHOR]

A total of 147 muscle spindles was studied histochemically in serial transverse sections of 42 cat tenuissimus muscle specimens. Nuclear bag, nuclear bag and nuclear chain intrafusal muscle fibers were distinguished by the differential staining resulting from the reactions for myosin adenosine 5′-triphosphatase and nicotinamide adenine dinucleotide tetrazolium reductase. The majority of intrafusal fibers were of the same histochemical type at both fiber poles. However, seven muscle spindles contained one nuclear bag fiber each that presented as a bag in one pole and as a bag in the other pole. These 'mixed' nuclear bag fibers were found in spindles that also contained at least one bag and one bag fiber of equivalent histochemical presentation in both fiber poles. The 'mixed' bag fibers displayed differences of apparent fiber diameter and relative polar length between the two fiber poles. The motor innervation pattern, as revealed by staining for cholinesterase, was also dissimilar between the two poles of 'mixed' bag fibers. The study indicates that the spindle equatorial region may in some instances serve as a boundary between two morphologically and histochemically different poles of the same intrafusal fiber. [ABSTRACT FROM AUTHOR]

Muscle spindles were traced in serial transverse sections of cat tenuissimus muscles. 'Myofibrillar' adenosine triphosphatase staining reaction was used to identify nuclear bag, nuclear bag and nuclear chain intrafusal muscle fibers. Typical chain fibers and long chain fibers were distinguished, the latter extending for more than 1,000 μm beyond the termination of the spindle capsule. Simple 'rim' and more elaborate 'plate' deposits were demonstrated histochemically along the poles of the typical chain fibers in staining for cholinesterases. They were considered to correspond, respectively, to the trail and plate motor nerve terminals. Most long chain fibers and the majority of nuclear bag fibers had their motor innervation limited to 'plate'-type endings. In addition, faint diffuse cholinesterase staining occurred along the spindle capsule and the surface of some intrafusal fibers. These histochemical observations are discussed with regard to the current concepts concerning the morphological and functional organization of the motor innervation of the cat muscle spindle. [ABSTRACT FROM AUTHOR]

Dorsal root ganglia L, L were removed to accomplish long-term (1 year) de-afferentation of the rat soleus muscle. Muscle spindles in the muscles deprived of sensory innervation were morphologically and histochemically abnormal. The spindle periaxial fluid space was greatly diminished with a thicker capsular investment. De-afferented intrafusal muscle fibers lacked either 'nuclear bags' or 'nuclear chains' at their midlengths. The intracapsular myofibrillar ATPase staining pattern of de-afferented nuclear bag fibers resembled that which the bag fibers normally display in their extracapsular regions. These abnormalities are discussed with respect to the regulatory functions of spindle sensory and motor nerves. [ABSTRACT FROM AUTHOR]

Cobalt and nickel evaporation rates between 1420° and 1600°K were measured by the effusion method in six Co-Ni alloys covering the whole concentration range. The partial thermodynamic functions in the Co-Ni system for nickel and cobalt were obtained by processing data simultaneously for both the components so that the Duhem-Margules equation was fulfilled. The investigated system shows slight negative deviations from Raoult's law. [ABSTRACT FROM AUTHOR]

A technique to measure ozone fluxes of 10[sup 14]-10[sup 16] cm[sup -2] s[sup -1] using a thin silver film deposited on a quartz-crystal deposition-rate monitor is described. The technique involves measuring the rate of mass increase of the silver film due to oxidation when it is first exposed to ozone. Ozone is found to be an extremely efficient oxidant for silver at room temperature. By establishing an independent measure of the incident ozone flux the product of our ozone purity and intrinsic detection efficiency has been determined to be 26±5%. [ABSTRACT FROM AUTHOR]

Superconducting thin films of Bi-Sr-Ca-Cu-oxides have been reproducibly prepared by reactive magnetically enhanced triode sputtering using three separate metal targets (Sr, Ca, and Cu-Bi). Oxygen was introduced directly at the substrates during film growth. The films were deposited on ambient temperature substrates [Al2O3, SrTiO3, and yttria-stabilized zirconia (YSZ)] and had thicknesses of 0.5–1.5 μm. After deposition, the films were annealed at 850–900 °C in flowing oxygen. The electrical resistance of the best films on YSZ decreased approximately linearly with temperature until the onset of superconductivity at about 85 K. Zero resistance was achieved by 74 K. Critical current densities in excess of 5×105 A/cm2 at 4.2 K were also obtained. X-ray diffraction demonstrated that the best films were nearly single phase (Bi2Sr2Ca1Cu2O8+x) and textured with the c axis perpendicular to the substrate. The effect of composition and annealing on our results is discussed. [ABSTRACT FROM AUTHOR]