Line Defects in Molybdenum Disulfide Layers

Layered molecular materials and especially MoS2 are already accepted as promising candidates for nanoelectronics. In contrast to the bulk material, the observed electron mobility in single-layer MoS2 is unexpectedly low. Here we reveal the occurrence of intrinsic defects in MoS2 layers, known as inversion domains, where the layer changes its direction through a line defect. The line defects are observed experimentally by atomic resolution TEM. The structures were modeled and the stability and electronic properties of the defects were calculated using quantum-mechanical calculations based on the Density-Functional Tight-Binding method. The results of these calculations indicate the occurrence of new states within the band gap of the semiconducting MoS2. The most stable non-stoichiometric defect structures are observed experimentally, one of which contains metallic Mo-Mo bonds and another one bridging S atoms

Explaining Myanmar's Regime Transition: The Periphery is Central

In 2010, Myanmar (Burma) held its first elections after 22 years of direct military rule. Few compelling explanations for this regime transition have emerged. This article critiques popular accounts and potential explanations generated by theories of authoritarian ‘regime breakdown’ and ‘regime maintenance’. It returns instead to the classical literature on military intervention and withdrawal. Military regimes, when not terminated by internal factionalism or external unrest, typically liberalise once they feel they have sufficiently addressed the crises that prompted their seizure of power. This was the case in Myanmar. The military intervened for fear that political unrest and ethnic-minority separatist insurgencies would destroy Myanmar’s always-fragile territorial integrity and sovereignty. Far from suddenly liberalising in 2010, the regime sought to create a ‘disciplined democracy’ to safeguard its preferred social and political order twice before, but was thwarted by societal opposition. Its success in 2010 stemmed from a strategy of coercive state-building and economic incorporation via ‘ceasefire capitalism’, which weakened and co-opted much of the opposition. Having altered the balance of forces in its favour, the regime felt sufficiently confident to impose its preferred settlement. However, the transition neither reflected total ‘victory’ for the military nor secured a genuine or lasting peace

An investigative study of the present professional preparation for teachers in primary schools in Saudi Arabia, with especial reference to Islamic and Arabic subjects

The central aim of this thesis was to examine the experience of the kingdom of Saudi Arabia in the preparation and training of prospective Arabic and Islamic primary teachers at the Teachers' Colleges with special attention to professional preparation, as perceived by Arabic and Islamic student teachers, teaching staff and officials in the Ministry of Education, and also the Deans and Vice- Deans of Teachers' Colleges.The study incorporates a full review of literature concerning the pre-service teacher training programme in general and in Arabic and Islamic subjects in particular. A profile of Saudi Arabia and its modern educational system is presented, while the core concepts of Islamic education and related issues are also discussed, and the situation of Arabic and Islamic subjects in Saudi schools is described.The key contribution of the thesis is an evaluation of the Arabic and Islamic teacher training programme in the Teachers' colleges, drawing on the available documents and regulations, and on the questionnaire survey of 127 Arabic and Islamic student teachers and 346 teaching staff from Arabic, Islamic and Education departments in Teachers' colleges. Their perspectives are complemented by information and opinions obtained through interviews with college Deans and Vice-Deans, and relevant ministerial officials.The survey returns and interviews revealed a number of problems. Respondents indicated dissatisfaction with several aspects of the teacher training programmes, particularly those associated with teaching practice. Imbalance and lacunae in the curriculum, inadequate facilities, poor preparation for the practicum, and deficiencies in the supervision and evaluation of teaching practice were among the problems highlighted. Appropriate remedies are recommenced to improve the status and quality of teacher training and future research priorities are also identified

Ornate manuals or practical adab? Some reflections on a unique work by an anonymous author of the 10th century CE.

This article addresses key concepts pertaining to Adab on the one hand and Abbasid administrative practices on the other, by focusing on an unpublished work that straddles both themes. It is shown that Arabic works on both Adab and bureaucracy are difficult to isolate and categorise conclusively as both genres were receptive to diverse flavourings, be they of an ornamental or of a strictly practical nature. Although the article adopts a comparative approach to these issues, detailed attention is paid to the character of the particular work under discussion and its author.Este artículo estudia conceptos claves que se encuentran, por un lado, en el Adab y por otro en las prácticas administrativas abbasíes a partir de una obra inédita que versa sobre ambas cuestiones. Muestra la dificultad de aislar y de colocar en categorías diferentes las obras de Adab y las dedicadas a la burocracia, ya que ambos géneros eran susceptibles de una coloratura tanto ornamental como estrictamente práctica. Aunque el artículo adopta una metodología comparativa, se dedica atención particular a la obra discutida y a su autor

Strategi Kepemimpinan Kepala Sekolah dalam Meningkatkan Kualitas Kinerja Guru di SMA 7 Sarolangun

Pemimpin pendidikan dilingkungan sekolah yaitu kepala sekolah.  Seorang pemimpin harus mampu menciptakan iklim dan suasana yang kondusif, aman, nyaman, tentram, menyenangkan penuh semangat untuk guru, karyawan dan siswa sekolah. Penelitian ini bertujuan untuk mendeskrpsikan strategi kepemimpinan kepala sekolah SMA 7 Sarolangun dalam meningkat kualitas kinerja guru. Penelitian ini menggunakan deskriptif kualitatif, subjek dalam penelitian ini adalah kepala sekolah dan guru. Teknik pengumpulan data menggunakan observasi, wawancara dan studi dokumen. Hasil penelitian menunjukkan bahwa strategi kepala sekolah yaitu (1) perencanaan pembelajaran dalam hal ini, kepala sekolah menerapkan bebrapa teknik untuk membantu guru dalam mengembangkan perencanaan pembelajaran, meliputi (a) Pembinaan Kinerja Guru, (b) Diklat. (2) Pelaksanaan pembelajaran, strategi yang digunakan kepala sekolah meliputi (a) Pengawasan pertama (b) sarana memfasilitasi (c) ikut serta dalam keluasan, (d) pemberian motivasi (e) pemberian penghargaan. (3) Evaluasi

Clinico-radiographic Studies on The Prevalent Distal Limb Affections in Working Equine at Luxor City

To illustrate the clinical and radiographic findings of some distal limbs affections in Ninety two animals (24 horses and 68 donkeys) which were admitted to Animal Care Hospital in Luxor. Each animal was subjected to thorough clinical and radiographic examination; the grade of lameness was recorded and the best radiographic views were taken.  Fifteen types of distal limb affections were evident. The most prevalent affections in donkeys were high and low ring bone (29.35%) and hoof abscess ( 9.78%) followed by traumatic arthritis of the fetlock (6.52%), suspensory ligament desmitis (5.43%), fracture of first phalanx (5.43%), fracture of PII (4.35%), side bone (3.26%)  whereas, fracture of metacarpal bone (1.09%), sesamoditis (1.09%) and flexural deformities (1.09%)  represented the lowest prevalent affections.On the other hand, side bone (4.35%), fracture of the metacarpal bone (4.35%) represented the most prevalent affections in horses followed by high and low ring bone (3.26%), fractures of PI (2.17%), PII (2.17%), subluxation of coronopedal joint (2.17%) and punctured wounds in of the hoof (2.17%), traumatic arthritis of the fetlock joint (2.17%). Whereas, navicular disease (1.09%), suspensory ligament desmitis (1.09%) and hoof abscess (1.09%) were the lowest prevalent affections in horses. Treatment was not recommended in certain cases. In conclusion, although the wide stride progress have made in diagnostic imaging in recent decades, the x ray still offers a satisfactory tool for diagnostic imaging in equine limb practice that is useful for equine practitioners

Enhanced Long-Path Electrical Conduction in ZnO Nanowire Array Devices Grown via Defect-Driven Nucleation

Vertical arrays of nanostructures have been widely used as major components in some of the most ground-breaking modern research-based devices, and ZnO nanowires have received particular attention because of their favorable electronic properties. Using a local multiprobe technique to measure the properties of individual ZnO nanowires in vertical arrays, we show for the first time that for metal-catalyzed ZnO nanowire growth the electrical contribution of individual wires to a device is highly dependent on the fate of the catalyst nanoparticle during growth. To overcome the limitations of metal-catalyzed growth, nanowires grown from a defect-driven nucleation process are shown to provide high-quality device structures with excellent long-path electrical conduction

Capture the growth kinetics of CVD growth of two-dimensional MoS 2

Understanding the microscopic mechanism is fundamental for function-oriented controlled chemical vapor deposition growth of two-dimensional (2D) materials. In this work, we reveal the growth kinetics of 2D MoS2 by capturing the nucleation seeds, evolving morphology, edge structure, and edge terminations at the atomic scale during chemical vapor deposition growth using the transmission electron microscopy and scanning transmission electron microscopy. The direct growth of few-layer and mono-layer MoS2 onto graphene-based transmission electron microscopy grids helped us to perform the subsequent transmission electron microscopy characterization without any solution-based transfer. Two seeding centers are observed: (i) Mo-oxysulfide (MoO x S2−y ) nanoparticles either in multi-shelled fullerene-like structures or as compact nanocrystals for the growth of fewer-layer MoS2; (ii) Mo-S atomic clusters. In the early stage growth, irregular polygons with two primary edge terminations, S-Mo Klein edges and Mo zigzag edges, appear approximately in equal numbers. The morphology evolves into a near-triangle shape in which Mo zigzag edges predominate. Results from density-functional theory calculations are consistent with the inferred growth kinetics, and thus support the growth mechanism we proposed. In general, the growth mechanisms found here should also be applicable in other 2D materials, such as MoSe2, WS2 and WSe2