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In spin Hall nano-oscillators (SHNOs), pure spin currents drive local regions of magnetic films and nanostructures into auto-oscillating precession. If such regions are placed in close proximity to each other they can interact and may mutually synchronize. Here, we demonstrate robust mutual synchronization of two-dimensional SHNO arrays ranging from 2 × 2 to 8 × 8 nano-constrictions, observed both electrically and using micro-Brillouin light scattering microscopy. On short time scales, where the auto-oscillation linewidth $$\Delta f$$ is governed by white noise, the signal quality factor, $$Q=f/\Delta f$$, increases linearly with the number of mutually synchronized nano-constrictions (N), reaching 170,000 in the largest arrays. We also show that SHNO arrays exposed to two independently tuned microwave frequencies exhibit the same synchronization maps as can be used for neuromorphic vowel recognition. Our demonstrations may hence enable the use of SHNO arrays in two-dimensional oscillator networks for high-quality microwave signal generation and ultra-fast neuromorphic computing. Synchronization of oscillators can be used to carry out cognitive tasks. Large two-dimensional arrays of synchronized spin Hall nano-oscillators have now been demonstrated, and may in future enable neuromorphic computing on the nanoscale.

Magnonics is the field of science investigating the physical properties of spin waves and utilizing them for data processing. Scalability down to the atomic dimensions, operations from the GHz to THz frequency range, utilization of the pronounced nonlinear and nonreciprocal phenomena, compatibility with CMOS are just a few of many advantages offered by magnons. Although magnonics is still primarily positioned in the academic domain, the scope of the scientific and technological challenges covered by the field are extensively investigated and many proof-of-concept prototypes have already been realized in the laboratory. This Roadmap is a product of the collective work of many Authors, covering versatile spin-wave computing approaches, their conceptual building blocks, and the underlying physical mechanisms. In particular, the Roadmap discusses the computation operations with Boolean digital data, unconventional approaches like neuromorphic computing, and the progress towards magnon-based quantum computing. The article is organized as a collection of subsections grouped into seven large thematic sections. Each subsection is prepared by one or a group of Authors and concludes with a brief description of the current challenges and the outlook of the further evolution of the research directions.

Electron spin resonance (ESR) spectroscopy was used todeterminethe effect of dry hopping on the oxidative stability and antioxidative potential of beer.Commercial beerwasdry-hopped at 5 °C and 20 °Cwith six hop varieties (Polish and American). The rate of radical formation and lag time were found to depend on the variety of hop used. An increase in the lag time and a decrease in the rate of radical formation occurred when dry-hopping was performed at 20 °C for all hop varieties (at 5 °C in some varieties). The lag time had a strong correlation with the TPC (total polyphenols content) in beer. The rate of radical formation was correlated with the iron content of the beer. A decrease in iron concentration was observed after dry-hopping at 20 °C. Overall, the evaluation of free radical formation using ESR is useful for predicting oxidative changes in beer during storage.

Artykuł dotyczy nieznanych powszechniej wileńskich rękopisów związanych z Leonem Borowskim. Autorka opisuje je i identyfikuje jako fragmenty przekładów Don Kichota Cervantesa oraz rozprawy teoretycznej Entwurf einer Theorie und Literatur der schönen Redekünste Johanna Joachima Eschenburga. Dokumenty dotyczące Borowskiego oraz dyskusje (Jana Śniadeckiego i Gotfryda Ernesta Groddecka) poświęcone nauce o literaturze, stanowiące kontekst jego działalności, są punktem wyjścia do refleksji teoretycznej na temat „tekstu” jako „faktu literaturoznawczego”: postulowanej dwuaspektowości jego badania, procesu jego konstruowania oraz warunków jego wejścia do obiegu naukowego. Markowska-Fulara explores the rather little-known Vilnius manuscripts associated with Leon Borowski. She describes them and identifies them as passages of a translation of Cervantes’ Don Quixote as well as of Johann Joachim Eschenburg’s treatise Entwurf einer Theorie und Literatur der schonen Redekunste. To contextualise Borowski’s work Markowska-Fulara presents documents that concern him as well as discussions (by Jan Śniadecki and Gottfried Ernst Groddeck) on literary scholarship. This leads to a theoretical exploration of the “text” as a “literary scholarly fact”: the postulated dual aspects of researching it, the process of constructing it and the conditions of its circulation among scholars.

The main aim of this article is to present the experimental data of the operating parameters and emissions obtained in a small gas turbine equipped with a variable area nozzle system. The variable area nozzle is proposed as a means of improving turbine efficiency, which has been a popular trend in recent development of gas turbine engines. Based on turbine vane twisting, the proposed variable area nozzle system was developed and implemented in GTM-120 small gas turbine. The concept was experimentally investigated on the engine test bench and engine working parameters were accurately measured. Experimental research shows that significant improvement of engine specific fuel consumption (up to 4%) and specific thrust (up to 5%) has been achieved. Additionally, reduction in CO emissions (up to 64%), NO emissions (up to 7%) and NO2 emissions (up to 53%) has been noted. Experimental research results were compared with analytical engine model showing moderate, qualitative agreement between the experimental data and model outputs. Main advantages of variable area nozzle system and design challenges of the proposed concept are discussed in the article summary.

Gesture controlled vehicle is a type of robot which can operated by human hand movements. The user needs to wear a glove which consists of transmitter and sensors like IR sensor. These sensors help in recording the movement of hand in a desired direction which ultimately results in the motion of robot or vehicle. It will be very easy for user to interact with car or robot more easily due to wire free connectivity. Vehicle can be controlled with the help of accelerometer sensor which is connected to hand glove. This will help the applicant to control the forward, backward and sideways movements. We have made the cross connections of motors which will help in the movement of tyres so that vehicle can take a sharp turn without any difficulty. Hand gesture controlled driverless vehicle is developed with the help of Arduino Nano, three-axis accelerometer, RF transmitter and receiver module..

प्रस्तुत आलेखमा हरि साई कृस्न साईको भारतको सङ्कलन गरी अध्ययन गरिएको छ । यस क्रममा सङ्कलनस्थल, प्रमुख बाचक र सहभागीहरूको परिचय दिई भारतको परिचय, पाठ, सन्दर्भ र आशय अर्थात् निष्कर्ष दिइएकोछ । प्रत्येक पृष्ठको अन्त्यमा उक्त पृष्ठमा प्रयुक्त स्थानीय कठिन शब्दहरूको नेपाली भाषामा अर्थ खुलाइएको छ ।

Ferromagnetic materials dominate as the magnetically active element in spintronic devices, but come with drawbacks such as large stray fields, and low operational frequencies. Compensated ferrimagnets provide an alternative as they combine the ultrafast magnetization dynamics of antiferromagnets with a ferromagnet-like spin-orbit-torque (SOT) behavior. However to use ferrimagnets in spintronic devices their advantageous properties must be retained also in ultrathin films (t < 10 nm). In this study, ferrimagnetic Gdx(Fe87.5Co12.5)1-x thin films in the thickness range t = 2-20 nm were grown on high resistance Si(100) substrates and studied using broadband ferromagnetic resonance measurements at room temperature. By tuning their stoichiometry, a nearly compensated behavior is observed in 2 nm Gdx(Fe87.5Co12.5)1-x ultrathin films for the first time, with an effective magnetization of Meff = 0.02 T and a low effective Gilbert damping constant of {\alpha} = 0.0078, comparable to the lowest values reported so far in 30 nm films. These results show great promise for the development of ultrafast and energy efficient ferrimagnetic spintronic devices., Comment: 7 Pages, 4 Figures

Introduction: Toxic multinodular goitre, first described by H.S. Plummer in 1913, is unremitting and often develops slowly, with more subtle symptoms than Graves’ disease. Cardiac symptoms such as tachycardia, heart failure, or arrhythmia and atrial fibrillation are most frequent. Here we describe a case who presented with symptoms of thyroid enlargement and heart failure. Case report: A 48-year old female presented to us with complaints of dysphagia, hoarseness of voice, breathlessness on exertion and palpitations since one month ago. Furthermore, the patient gave history of swelling of the neck which was initially pea sized and gradually increased to the current size over a period of two months. On examining the swelling of the neck, thyroid gland appears enlarged, firm with multiple nodules. Two-dimensional echocardiography revealed a dilated left ventricle with generalized hypokinesia. Computed Tomography of the neck suggested enlarged thyroid gland (12.1 cm × 6.5 cm) with heterogenous architecture, and thyroid gland encircling the trachea for approximately 270 degree with mass effect. Thyroid scan showed multinodular goitre with multiple hyperfunctioning nodules of both lobes and warm nodules only in left lobe. The patient was diagnosed as multinodular goitre with cardiomyopathy. The patient was treated medically with methimazole, propranolol, aspirin, ramipril, sustained release urodeoxycholic acid, rosuvastatin, pantoprazole and multivitamin. The patient underwent near total thyroidectomy with radioactive iodine ablation, as and when required. Conclusion: Patients with toxic multinodular goitre very frequently present with cardiovascular symptoms, which when identified and treated early can reduce the morbidity significantly.

Synchronization of large spin Hall nano-oscillator (SHNO) arrays is an appealing approach toward ultrafast non-conventional computing. However, interfacing to the array, tuning its individual oscillators and providing built-in memory units remain substantial challenges. Here, we address these challenges using memristive gating of W/CoFeB/MgO/AlOx-based SHNOs. In its high resistance state, the memristor modulates the perpendicular magnetic anisotropy at the CoFeB/MgO interface by the applied electric field. In its low resistance state the memristor adds or subtracts current to the SHNO drive. Both electric field and current control affect the SHNO auto-oscillation mode and frequency, allowing us to reversibly turn on/off mutual synchronization in chains of four SHNOs. We also demonstrate that two individually controlled memristors can be used to tune a four-SHNO chain into differently synchronized states. Memristor gating is therefore an efficient approach to input, tune and store the state of SHNO arrays for non-conventional computing models.

ABSTACTThe type II secretion system (T2SS) is a multiprotein machinery spanning the diderm of gram-negative bacteria. T2SS contributes to the virulence of numerous gram-negative pathogens, including the multidrug resistant species Pseudomonas aeruginosa, Acinetobacter baumanii, Klebsiella pneumonia and Vibrio cholerae. Even though the T2SS has been studied extensively over the past three decades, our understanding of the molecular basis of its biogenesis and of its overall structure still remains unclear. Here we show that the core component of the inner membrane platform, the GspLM membrane protein complex, can be isolated as a dimer of dimers. Importantly, the complex is able to bind the T2SS ATPase, GspE, with high affinity. Finally, we have developed single domain VHH camelid antibodies (nanobodies) against the GspLM complex and have identified a nanobody that effectively prevents the cytoplasmic domain of GspL, GspLcyto, from binding to GspE. Our findings suggest that the T2SS ATPase is permanently associated with the inner membrane platform and that the GspELM complex should be considered as a key subassembly for the biogenesis of the T2SS apparatus.

We demonstrate the compositional effect on the magnetodynamic and auto-oscillations properties of Ni100-xFex/Pt (x= 10 to 40) nanoconstriction based spin Hall nano-oscillators. Using spin-torque ferromagnetic resonance (ST-FMR) performed on microstrips, we measure a significant reduction in both damping and spin Hall efficiency with increasing Fe content, which lowers the spin pumping contribution. The strong compositional effect on spin Hall efficiency is primarily attributed to the increased saturation magnetization in Fe-rich devices. As a direct consequence, higher current densities are required to drive spin-wave auto-oscillations at higher microwave frequencies in Fe-rich nano-constriction devices. Our results establish the critical role of the compositional effect in engineering the magnetodynamic and auto-oscillation properties of spin Hall devices for microwav eand magnonic applications.

Short wavelength exchange-dominated propagating spin waves will enable magnonic devices to operate at higher frequencies and higher data transmission rates. While giant magnetoresistance (GMR)-based magnetic nanocontacts are efficient injectors of propagating spin waves, the generated wavelengths are 2.6 times the nano-contact diameter, and the electrical signal strength remains too weak for applications. Here we demonstrate nano-contact-based spin wave generation in magnetic tunnel junctions and observe large-frequency steps consistent with the hitherto ignored possibility of second- and third-order propagating spin waves with wavelengths of 120 and 74 nm, i.e., much smaller than the 150-nm nanocontact. Mutual synchronization is also observed on all three propagating modes. These higher-order propagating spin waves will enable magnonic devices to operate at much higher frequencies and greatly increase their transmission rates and spin wave propagating lengths, both proportional to the much higher group velocity., Nano-contact-based spin wave generation may enable high-frequency magnonic devices but has been limited to long wavelengths and weak signal strengths. Here the authors demonstrate high-order short-wavelength propagating spin waves with increased transmission rates and propagation lengths in magnetic tunnel junction stacks.

We present and discuss here the observations of a small long duration GOES B-class flare associated with a quiescent filament eruption, a global EUV wave and a CME on 2011 May 11. The event was well observed by the Solar Dynamics Observatory (SDO), GONG H α , STEREO and Culgoora spectrograph. As the filament erupted, ahead of the filament we observed the propagation of EIT wave fronts, as well as two flare ribbons on both sides of the polarity inversion line (PIL) on the solar surface. The observations show the co-existence of two types of EUV waves, i.e., a fast and a slow one. A type II radio burst with up to the third harmonic component was also associated with this event. The evolution of photospheric magnetic field showed flux emergence and cancellation at the filament site before its eruption.

We provide solutions to Einsteins field equations for a model of a spherically symmetric anisotropic fluid distribution, relevant to the description of compact stars. The central matter-energy density, radial and tangential pressures, red shift and speed of sound are positive definite and are decreasing monotonically with increasing radial distance from the center of matter distribution of astrophysical object. The causality condition is satisfied for complete fluid distribution. The central value of anisotropy is zero and is increasing monotonically with increasing radial distance from the center of the distribution. The adiabatic index is increasing with increasing radius of spherical fluid distribution. The stability conditions in relativistic compact star are also discussed in our investigation. The solution is representing the realistic objects such as SAXJ1808.4-3658, HerX-1, 4U1538-52, LMC X-4, CenX-3, VelaX-1, PSRJ1614-2230 and PSRJ0348+0432 with suitable conditions.

This study examines whether the positive and negative shocks in world commodity prices transmit symmetrically to the domestic prices of GCC economies while using threshold autoregressive (TAR) model. The empirical results indicate that the positive shocks in world prices do transmit to the domestic prices of these economies whereas, the negative shocks are not transmitted. Moreover, for certain commodity-groups, which respond to both positive and negative shocks, the speed of transmission is relatively faster with respect to the positive shocks as compared to negative shocks. These findings indicate that the agents in these economies prefer to choose inaction in response to negative world price shocks whereas, the positive shocks of even smaller size trigger quicker upward adjustments in the domestic prices. Consistent with the predictions of menu cost models, these results imply that the shocks in world prices which raise the desired level of domestic prices, cause quick and large increase in domestic prices whereas the shocks that lower the desired prices, cause a small or no decrease in these prices. These results underline the fact that despite adopting a number of trade reforms, the markets of these economies are still characterized with lower degrees of competitiveness, higher imperfections and other related inefficiencies.

Leptospiroisis presents with a wide range of clinical symptoms, ranging from mild disease symptoms to life threatening complications. The clinical features and routine laboratory findings are not specific, and therefore a high index of suspicion must be maintained for the diagnosis. We documented a case of a patient, who presented with high grade fever, diarrhea, vomiting, had icterus on examination. Initial laboratory investigations revealed low platelet count, along with raised liver enzymes. IgM leptospirosis came positive and patients received broad spectrum antimicrobials and supportive fluid therapy. During admission, patient developed sudden onset breathlessness, which was diagnosed as acute respiratory distress syndrome after doing immediate arterial blood gases. The patient received noninvasive ventilation with positive airway pressure, from which the patient eventually recovered. Most of the cases of leptospirosis are uneventful with complete recovery. However, a minority of these cases may end with life threatening complications. A vaccine for human use is not available in most countries. Therefore, the prevention involves reducing exposure, either by avoiding situations that pose a risk of transmission or using protective clothing.

Primary hyperaldosteronism is not as uncommon as we thought, and by recent estimates the prevalance may be as high as 11% among hypertensives. We present a case of a 33 years old male patient came with a complaint of headache in occipital area & weakness in both lower limb since 4 weeks. The patient was a diagnosed case of hypertension and was already on tablet Atenolol (25 mg) once a day. At the time of admission, the patient was found to have a pulse of 96/min and blood pressure of 170/100 mm of Hg. Power was 3/5 for both right and left lower limbs. At the time of admission, serum potassium was 2.8. As a result, the patient was shifted to tablet Metroprolol and Amlodipine (50 + 5 mg) once a day. We also added tablet Cilnidipine (10 mg) and Telmisartan (80 mg) once a day and syrup Potklor thrice a day with water. The patient was sent for renal artery doppler, urine for metanephrines and vanillylmandelic acid, serum aldosterone, plasma aldosterone/plasma renin activity ratio (PAC/PRA ratio), urinary aldosterone, urinary cortisol and adrenocorticotrophic hormone level and computed tomography (CT) abdomen to rule out hyperaldostronism. Plasma aldosterone/plasma renin activity ratio, urinary aldosterone was high and CT abdomen revealed a solitary nodule in the left adrenal gland measuring 1.2 × 1.0 cm in maximum transverse diameter, which was suggestive of adrenal adenoma. Diagnosis of Conn’s syndrome secondary to adrenal adenoma was made. The patient was advised tablet Aldactone (25 mg) once a day and serum electrolytes were repeated which showed normalization with normal blood pressure.