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The present study investigated the diversity of culturable rhizobacteria associated with potato (S. tuberosum L.) in Tanzania and assessed their in vitro plant growth-promoting (PGP) activities to deduce their potential as biofertilizers. Potato rhizosphere soil and tuber samples (54 samples in total) were collected from 9 villages in three different agro-ecological regions in Tanzania. A total of 145 rhizobacterial isolates were obtained, 52 of which were selected and identified by partial 16S rRNA gene sequences and screened for various PGP traits in vitro including qualitative and quantitative solubilization of phosphorus (P), zinc (Zn) and potassium (K), nitrogen (N2) fixation and production of ammonia (NH3) in nitrogen-free medium, and indole-3-acetic acid (IAA), gibberellic acids (GA) and siderophores production. The results showed that the isolates were all Gammaproteobacteria, belonging to 4 families (Enterobacteriaceae, Yersiniaceae, Pseudomonadaceae and Morganellaceae) and 9 genera (Enterobacter, Klebsiella, Serratia, Pseudomonas, Morganella, Buttiauxella, Pantoea and Cedecea). Significant differences (P < 0.05) were observed for all assessed PGP abilities of the external and endophytic rhizobacterial isolates except for quantitative siderophore production and qualitative P and K solubilization for the external rhizobacteria and production of IAA and GA for the endophytic rhizobacteria. Among the best PGP isolates which can be exploited for biofertilization of the potato were Klebsiella pneumoniae KIBS1, K. grimontii LUTS10, Serratia liquefaciens KIBT1, Enterobacter ludwigii KIBS10 and Citrobacter freundii MWALS6. Comparative evaluation of PGP abilities of these two groups of isolates revealed significant differences (P < 0.05) only for NH3 and IAA production and qualitative K solubilization. [ABSTRACT FROM AUTHOR]

The gyrotropic rotation around the equilibrium position constitutes the fundamental excitation of magnetic vortices in nanostructures. The frequency of this mode varies with material and sample geometry, but is independent of the vortex handedness and its core direction. Here, we demonstrate that this degeneracy is lifted in a spin-torque oscillator containing two vortices stacked on top of each other. When driven by spin-polarized currents, such devices exhibit a set of dynamic modes with discretely split frequencies, each corresponding to a specific combination of vorticities and relative core polarities. The fine splitting occurs even in the absence of external fields, demonstrating that such devices can function as zero-field, multi-channel, nano-oscillators for communication technologies. It also facilitates the detection of the relative core polarization and allows for the eight non-degenerate configurations to be distinguished electrically, which may enable the design of multi-state memory devices based on double-vortex nanopillars. [ABSTRACT FROM AUTHOR]

Introduction: Aim of this study was to evaluate outcomes of operative as compared to conserveative treatment for two-part humerus fractures at the surgical neck. Methods: Data from a prospective multi-centre cohort study on four treatment options (conservative treatment and three implants, i.e. LPHP, PHILOS and PHN) for proximal humerus fractures were evaluated in this post hoc analysis. All patients with two-part fractures of the surgical neck (AO types A2, n = 54 and A3, n = 110) were identified and included for the analysis. All operatively treated patients were gathered and compared to those receiving conservative treatment. Primary outcome parameters were pain, range of motion and absolute and relative Constant scores at 3, 6 and 12 months following injury and coronal plane alignment at 12 months. Results : Operative ( n = 133) and non-operative ( n = 31) groups were comparable with regard to all parameters assessed including mean age (62.9 vs. 65.6, P = 0.479), gender (27 vs. 29 % male, P = 0.826) and fracture distribution (65 vs. 77 % A3 type, P = 0.207). 26 of the 31 conservatively treated and 103 of the 133 operatively treated patients (84 and 77 %, respectively) were available for final follow-up. There was a continuous improvement for all outcome parameters in both treatment groups ( P < 0.001). Operative treatment resulted in a more effective reduction of pain at 3 months (51 vs. 76 % reporting pain at fracture site, P = 0.03) and a reduction of coronal plane malalignment. Both range of motion and Constant scores were, however, comparable in both groups at all follow-up visits. Relative and absolute Constant scores were generally excellent at final follow-up (74 vs. 74, P = 0.528 and 89 vs. 91, P = 0.494, respectively). Conclusions: Both non-operative treatment and operative treatment using modern implants (LPHP, PHILOS and PHN) can be considered safe and effective treatment options for two-part fractures of the proximal humerus. Operative treatment may result in better range of motion and reduced pain in the early postoperative course of treatment. [ABSTRACT FROM AUTHOR]

The vortex state, characterized by a curling magnetization, is one of the equilibrium configurations of soft magnetic materials and occurs in thin ferromagnetic square and disk-shaped elements of micrometre size and below. The interplay between the magnetostatic and the exchange energy favours an in-plane, closed flux domain structure. This curling magnetization turns out of the plane at the centre of the vortex structure, in an area with a radius of about 10 nanometres—the vortex core. The vortex state has a specific excitation mode: the in-plane gyration of the vortex structure about its equilibrium position. The sense of gyration is determined by the vortex core polarization. Here we report on the controlled manipulation of the vortex core polarization by excitation with small bursts of an alternating magnetic field. The vortex motion was imaged by time-resolved scanning transmission X-ray microscopy. We demonstrate that the sense of gyration of the vortex structure can be reversed by applying short bursts of the sinusoidal excitation field with amplitude of about 1.5 mT. This reversal unambiguously indicates a switching of the out-of-plane core polarization. The observed switching mechanism, which can be understood in the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application in data storage. [ABSTRACT FROM AUTHOR]

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Copyright of Der Orthopäde is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sixteen referred patients were reviewed after excision of an unexpected soft-tissue sarcoma of the extremities. Eight tumors were located in the muscle deep to the fascia, and 8 lesions exceeded the size of 5 cm. The lack of awareness by the primary physician towards the possibility of a malignant lesion was striking, although 11 of 16 tumors presented as a newly formed mass. No imaging studies were done in 11 patients. Fine needle biopsy was unsuccessfully performed in 3 patients. Eleven lesions (63%) were high-grade. Resection margins were intralesional in 12 (75%) and marginal in 4 (25%) patients. Surgical oncologic rules were disregarded in 7 cases, including opening of probably uninvolved joints. Postoperative magnetic resonance imaging (MRI) scans showed ¶a poor negative predictive value for residual tumor. Repeated resection, including three amputations, revealed residual tumor in 10 patients (63%). Four patients received adjuvant local radiation, with additional chemotherapy in 2 of them. At an average follow-up of 4.5 years (range 15–149 months), 4 patients (25%) had developed distant metastases with a local recurrence in 3 (19%). There was one tumor-related death (6%). Physicians’ alertness towards the possible malignancy of an enlarging mass cannot be overemphasized. Evaluation by adequate imaging techniques, biopsy, and definitive resection and reconstruction should be performed by an oncologically trained orthopaedic surgeon. Inadequate primary excision leads to a high local recurrence rate and more mutilating surgery and obscures the long-term prognosis. [ABSTRACT FROM AUTHOR]

Based on 30 fresh cadaver dissections a detailed anatomic study of the medial malleolar network is presented with particular attention to the anastomoses between the latter and the vascular axis that follows the saphenous nerve. The medial malleolar network is formed by the anterior medial malleolar artery, branches from the medial tarsal arteries, the posterior medial malleolar artery and branches from the medial plantar artery. A distinct anterior medial malleolar artery and posterior medial malleolar artery could be identified in 80 and 20%, respectively, as well as constant additional small branches arising from the anterior tibial or posterior tibial artery. A constant anastomosis was found between the arcade formed by the medial tarsal arteries and the medial plantar a. in 60%, and the medial branch of the medial plantar artery in 40%, respectively. This anastomosis always gave rise to branches to the medial malleolar network. In the perimalleolar area and with regard to the great saphenous v. a larger anterior and a smaller posterior branch of the saphenous nerve was found in 100 and 90%, respectively. In all dissections, for both branches of the saphenous nerve two to four small, but distinct anastomoses between the medial malleolar network and the perineural vascular axis were identified. These constant anastomoses represent a new and reliable vascular base for the distally-based saphenous neurocutaneous island flap. Thus, the pivotal point of the flap can be chosen in the area of the medial malleolus without respecting the most distal septocutaneous anastomosis between the perineural vascular axis and the posterior tibial artery. Additionally, an illustrative clinical case is presented. [ABSTRACT FROM AUTHOR]

The timing of soft-tissue reconstruction for severe open fractures of the lower leg is considered crucial to the later outcome, and yet pertinent publications are few. The purpose of this study was to add some based on evidence arguments for the choice of the most adequate timing in the management of these injuries. Twenty-nine consecutive open fractures of the tibia, including 24 grade 3B and 5 grade 3C fractures, were treated using a protocol of immediate debridement, early definitive skeletal stabilisation and early soft-tissue reconstruction. Fifteen lower legs were reconstructed after a mean delay of 4.4 days (range 1–9 days), while 14 lower legs were reconstructed immediately, i.e. as an emergency procedure on the day of admission. Both groups were comparable for sex, age, type of trauma, associated general injuries, type of fracture, associated arterial lesion, associated tendon rupture, type of soft-tissue reconstruction and duration of follow-up. All patients were reviewed at a mean follow-up of 47 months (range 15–89 months). In the delayed reconstruction group the time to full, unprotected weight-bearing ( P = 0.0021), the time to definitive union ( P = 0.0049), the number of reoperations ( P = 0.0001) and the infection rate ( P = 0.0374) were significantly higher. The data suggest that immediate reconstruction is, the general condition of the patient permitting, the timing of choice for soft-tissue coverage. [ABSTRACT FROM AUTHOR]

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Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Surgical & Radiologic Anatomy is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The hypothesis was tested that reversible riboflavin (RF)-binding sites are part of the photoreceptor in Euglena gracilis. Published evidence shows that the phototactic stimulus - with a flavin-type action spectrum - is perceived at the paraflagellar body (PFB). Flagella with PFBs were isolated from Euglena gracilis by a combined cold and Ca shock. Saturable binding of [C]RF was demonstrated with such preparations, in the oxidized state as well as under reducing conditions in the presence of dithionite. Affinities for RF were high: K (oxidized)=0.08 μM, and K (reduced)=0.7 μM. Flavin mononucleotide and flavin adenine dinucleotide showed lower binding affinities. The in vitro RF binding per unit of protein was enriched approximately tenfold in the flagellar preparations when compared with homogenates of whole cells. The number of (reduced) binding sites per entire flagellum was determined to be in the order of 10. This number is in line with published estimates of chromophores bound in or at the PFB. [ABSTRACT FROM AUTHOR]

An auxin binding sive, with characteristics different from the previously described auxin binding sites I and II in maize coleoptiles, is reported in homogenates of zucchini ( Cucurbita pepo L. cv. Black Beauty) hypocotyls. Evidence from differential centrifugation and sucrose and metrizamide density gradients indicates that the site is localized on the plasma membrane. The site has a K of 1-2×10 M for indole acetic acid and has a pH optimum of 5.0. Binding specificity measured with several auxins, weak auxins, and anti-auxins generally parallels the activities of the same compounds as inhibitors of auxin transport. 1-N-naphthylphthalamic acid and 2,3,5-triiodobenzoic acid (2,3,5-TIBA), both auxin transport inhibitors in vivo, increase specific auxin binding to this site. 3,4,5-TIBA, which can partially reverse 2,3,5-TIBA's transport inhibition when the two substances are added together in vivo, partially reverses 2,3,5-TIBA's increase in specific auxin binding to the plasma membrane site when added with 2,3,5-TIBA in vitro. Preliminary investigations indicate that a similar plasma membrane site exists in maize ( Zea mays L.) coleoptiles. It is suggested that different conformations of this site may function during active auxin transport. [ABSTRACT FROM AUTHOR]

The mesentery preparation of normotensive rats (NR) (P97±4 mm Hg) and of spontaneously hypertensive rats (SHR) (161±2 mm Hg) of comparable age (20±3 weeks) was used to study morphological changes of the microvasculature in established hypertension. The arterioles, classified according to their branching order, had an increased inner diameter in SHR (by 20%). The smooth muscle hypertrophy decreased with smaller vessel size. Pre- and postcapillary vessels were shorter in SHR than in NR by 17 to 35%. The number of these vessels related to the number of the feeding terminal arterioles was found to be reduced by nearly 50% in SHR. The data suggest a lowered arteriolar flow resistance in individual vessels of the hypertensive group concomitant with a gradually disappearing smooth muscle hypertrophy towards the capillary bed. The elevation of the resistance to blood flow in the hypertensive rats is obviously caused by a reduced number of resistance vessels, as seen in the mesentery vascular bed. Similar results were obtained in the true capillaries, which showed greater inner diameters (SHR vs NR: 7.2 μm vs 6.4 μm), shortened lengths (141 vs 170 μm) and a reduced number (50 bs 70). Red cell velocity in true capillaries did not differ (0.51 mm/s vs 0.49 mm/s). Arterio-venous shunt vessels were described with an average inner diameter of 11 μm. In SHR these vessels were shorter (424 vs 654 μm) and increased in number. The 'hydraulic hindranc' of AV-shunt vessels and true capillaries together was decreased in SHR; the surface area did not differ between SHR (55.7 · 10 μm) and NR (50.1 · 10 μm) suggesting no major variation in the exchange functions. [ABSTRACT FROM AUTHOR]

When low concentrations (e.g. 10 M) of labelled 3-indoleacetic acid (C-IAA) or α-naphthaleneacetic acid (C-NAA) are added in vitro to homogenates of corn coleoptiles, radioactivity is reversibly bound to pelletable particles. From the saturation kinetics of the binding it is possible to estimate an apparent K between 10 M and 10 M and a concentration of specific sites of 10-10 M per tissue volume. The binding is auxin-specific. Among many compounds tested, only auxins and such auxin analogues that are known to interact directly with auxin in transport and/or growth were found to interfere with this binding. For instance, the growth-active d-dichlorophenoxyisopropionic acid at 10 M inhibits C-NAA binding more than the less active l-isomer. The auxin-binding fractions are practically free of DNA and cytochrome-C oxidase and contain binding sites for 1-naphthylphthalamic acid. The results are discussed in context with the hyothesis-derived mainly from physiological data-that auxin receptors are localized at the plasma membrane. [ABSTRACT FROM AUTHOR]

Plasma membrane-rich fractions were prepared from maize coleoptiles by low-shear homogenization and differential and sucrose-gradient centrifugation. Plasma membrane fragments were identified using a specific cytochemical stain based on phosphotungstic acid prepared in chromic acid. In a comparison of 10 different cell fractions of varying plasma membrane content, the N-1-napthylphthalamic-acid (NPA)-binding activity of the fractions was directly proportional to the content of plasma membrane. The NPA binding appears to be strong K between 10 and 10 M) but non-covalent. NPA is known to inhibit auxin transport efficiently and quickly. Thus, the results are consistent with the localization of auxin transport sites at the plasma membrane of plant cells. [ABSTRACT FROM AUTHOR]

In coleoptiles of the amylomaize corn mutant (AM), the amyloplasts are much reduced in size in comparison with the wild type corn (WT), permitting a comparison of geotropic responsiveness as related to lateral displacement of amyloplasts and lateral transport of auxin. The amyloplasts of AM showed 30-40% lesser lateral redistribution in response to horizontal exposure in comparison with WT. With geotropic stimulation, the lateral transport of auxin in the direction of growth was 40-80% less, and the geotropic curvature by the coleoptiles was also significantly less in the mutant as compared with WT. These correlations support the hypothesis that the starch plastids serve as gravity sensors in the geotropic responses of coleoptiles. [ABSTRACT FROM AUTHOR]

Within 20 min of its application, auxin enhances the transport processes that move auxin molecules through coleoptile tissue. The effect was observed after treatment with indoleacetic acid and α-naphthaleneacetic acid, but not with growth-inactive auxin analogues. [ABSTRACT FROM AUTHOR]

In an effort to examine the specificity of the auxin transport system, the movement of a variety of growth substances and of auxin analogues through corn coleoptile sections was measured in both the basipetal and acropetal directions. In contrast to the basipetal, polar transport of the auxins indoleacetic acid (IAA) and 2,4-dichlorophenoxyacetic acid, no such movement was found for benzoic acid or for gibberellin A. A comparison of the α- and β-isomers of naphthaleneacetic acid showed that the growth-active α-form is transported, but not the inactive β-analogue. Both the dextro (+) and leavo (-) isomer of 3-indole-2-methylacetic acid showed the basipetal movement characteristic of IAA, the dextro isomer being more readily transported than the (-)-form. In this instance, too, the transport was roughtly proportional to the growth promoting activity. The antiauxin p-chlorophenoxyisobutyric acid inhibited auxin transport as it inhibited auxin-induced growth. These results agree with the hypothesis that processes involved in auxin transport are closely linked to or even identical with the primary auxin action. [ABSTRACT FROM AUTHOR]

A defective phage Φ 80.1 was obtained which carries an amber suppressor locus ( su, most likely identical to su of Brenner and Beckwith, 1965) and part of the tryptophan operon from E. coli K 12. Various homo- and heterogenotes with respect to this suppressor locus have been isolated. The action of the amber suppressor locus on amber sites in the decarboxylase gene of the pyruvate dehydrogenase complex and on T 4 amber mutants was tested. In all cases the suppressor in its active state ( su; i. e., suppressing amber sites) was dominant over the suppressor in the inactive ( su) state. The presence of another amber suppressor ( su) in the host did not alter the expression of su towards T 4 amber mutants. Further evidence was obtained for the specificity of the amber suppression. While remaining unsuppressed in strains harboring su, two amber sites of the O-type in one of the pyruvate dehydrogenase genes are suppressed by su in heterogenotes su/ su. The kinetics of the expression of the suppressor locus after infection with the defective Φ 80.1 carrying su was tested and compared for the production of pyruvate dehydrogenase and T 4 amber mutants. Comparable rates of suppressed synthesis of the enzyme appeared to be reached much later than the formation of T 4 amber mutants. [ABSTRACT FROM AUTHOR]

Gene function of various T4-heterozygotes was tested. About half of the HETs containing wild type and an am-mutation disappeared under non-permissive conditions, if the am-defect concerned 'early' functions. The same was found when phages, heterozygous for r and an rII-point-mutation, were adsorbed to K12 (λ). A much more extensive loss of HETs in K could be observed if an rIIA- and an rIIB-point-mutation (block-mutations showed different results) occurred together in a non-recombinant heterozygote. The findings provide evidence that one class of T4-heterozygotes has a heteroduplex DNA-structure. [ABSTRACT FROM AUTHOR]

The analysis of the progeny from three-allelic, triparental one-factor crosses in T4 showed a fraction of phages carrying all three markers in one particle. These three-allelic heterozygotes were observed in the rII-region as well as in the host range gene. Their frequency (0.01-0.04% of total yield) was in the range expected from theory. This result is discussed with respect to the current picture of circular permutation in phage T4. [ABSTRACT FROM AUTHOR]

Copyright of Naunyn-Schmiedebergs Archiv für Experimentelle Pathologie und Pharmakologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Twenty-five years prior to presentation a 41-year-old man had a femoral fracture stabilized with a 4.5 mm AO/ASIF steel plate. The femur healed uneventfully and the patient was asymptomatic for the following 20 years. He then noticed a slow-growing swelling of the left thigh associated with a degree of weakness. Radiographs of the femur 25 years after fracture stabilization showed a massive expansive osteolytic process surrounded by a rim of bone. Magnetic resonance imaging (MRI) confirmed the presence of a large tumor. Since malignancy could not be excluded the patient underwent incisional biopsy. The histologic findings were nonspecific. Because of persistent symptoms the lesion was marginally excised. Intraoperatively a folded cotton sponge was found adjacent to the femur. Histopathologic investigation confirmed a foreign body reaction probably related to the retained cotton sponge. Reactive, foreign-body-induced change may mimic bone and or soft tissue malignancies. [ABSTRACT FROM AUTHOR]

Copyright of Surgical & Radiologic Anatomy is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Under intravital conditions, intravascular pressures of mesenteric resistance vessels were measured in normotensive (NR, mean blood pressure 92 mm Hg) and spontaneously hypertensive rats (SHR, 161 mm Hg) being elevated over all by about 75%; the tangential wall stress (σ=p·r/h; p represents the intravascular pressure and r/h the ratio of internal radius to wall thickness) was found to be increased by 120-140% in SHR. [ABSTRACT FROM AUTHOR]

Larvae and adults of the aphid Myzus persicae (Sulz.), reared on a synthetic diet, gain higher weight if their diet contains ATP (1.11 μ M). The numbers of larvae born on diets with ATP are higher (20%) than on diets without ATP. The longer aphids were fed on the ATP-diet the more their weight increased compared with larvae on a diet without ATP. Generally ATP seems to balance the synthetic diet in whatever physiological way it may be. Since phloem sap contains a high level of ATP, it is suggested that ATP may also be of great importance under natural conditions on the host-plants. [ABSTRACT FROM AUTHOR]