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The impact of the 2022 floods on Pakistan’s rural communities and agriculture has been devastating, resulting in the loss of crops, livestock, and essential infrastructure. The country is now facing an unprecedented food security crisis. Nationally, Pakistan’s Sindh Province accounts for 42% of the rice production, 23% of the cotton production, and 31% of the sugarcane production. In our report, we assess potential crop production losses for these crops at the sub-district level using a remote-sensing approach based on satellite imagery. The analyses are designed to support the Government of Pakistan's rehabilitation and compensation planning processes.

Mistletoe (Viscum album), a hemiparasite of Scots pine (Pinus sylvestris), is one of the major problems in the conservation of Scots pine forest in the Alps. The study area covered with coniferous plantation, a part of Bois Noir in the South Western French Alps is highly affected by mistletoe. Consequences of mistletoe infection include branch swelling and bending of the tree structure. The coniferous plantation in the study area, located in Bois Noir in the south-western French Alps, is experiencing an alarmingly high rate of tree mortality due to mistletoe infection. This study aims to assess the spectral distinctness of Scots pine in the presence and absence of mistletoe. For the management and minimization of biological invasion, detection and mapping plays a key role in forest conservation. Advancement of very high resolution (VHR) satellite imagery and aerial imagery with application of remote sensing and GIS technologies has shown a promising result in detecting, mapping and monitoring forest health. In this research, very high resolution satellite imagery WorldView-2 (panchromatic 0.5m and multispectral 2m) was used. Scots pine with mistletoe presence has low spectral reflectance in all bands, but NIR1, NIR2 and Red edge of WorldView-2 have higher ability to discriminate the mistletoe. Similarly, the vegetation index NDVI 2 (band combination of Red and NIR2) has the potential to discriminate the mistletoe. Detection of such biological invasions provides good information for effective conservation and better management of forests.

Since the declaration of COVID-19 pandemic by WHO on 13 March2020, over 210 countries / territories have had active cases and 1/3rd of the world’s population have been on complete lockdown or partial restriction. Main route of transmission of COVID-19 is through droplets like most communicable respiratory illnesses followed by infected surfaces. Public measures like wearing masks, social distancing, hand washing and other respiratory hygiene are being followed in unprecedented level and people are tested rapidly if they show symptoms of the disease such as fever, cough, fatigue, myalgia and dyspnea. These symptoms are similar to other respiratory diseases such as common flu, influenza, pneumonia and Tuberculosis. The preventive measures are also effective in these diseases. In Wuhan, China the lockdown lasted for 76 days and seems to follow similar course in other countries. The air pollution and travel has also decreased which will further decrease transmission of respiratory illnesses. These behavioral changes can get embedded into human cultures and play a vital role to decrease incidence of other respiratory illnesses. To measure the impact, we need to be observant and carry time series analysis of the pre and post pandemic data. With proper strategies this could be utilized as an opportunity to reduce burden of other respiratory communicable disease. Keywords: COVID-19, respiratory infection, social distancing, tuberculosis, influenza, lockdown

A heat exchanger and vegetable oil bubbling system was designed and tested for biomass-generated syngas cooling and cleaning. The fully enclosed heat exchanger contained water at 15 °C, with syngas having to travel 35 m3/s. Using canola oil, the bubbler was tested at 70 and 100 mm oil depths and 5 and 10 mm syngas bubble sizes to determine the effect of tar removal. The results showed that tar removal efficiency was significantly affected by oil depth and bubble size; however, the interaction between bubble size and oil depth was not significant. About 60% of tars was removed by the heat exchanger alone and 96% of the remaining tars was removed by the oil bubbler when used in series with the heat exchanger. Overall, tar reduction efficiency of 98.5% was achieved with the heat exchanger plus oil bubbler having oil depth of 100 mm and syngas bubble size of 5 mm. Heat exchanger removed most of the tars by cooling the syngas below its dew point but syngas tars with low dew point was absorbed in the oil bubbler.

Forest fire is one of the major global environmental issues, causing havoc in places as disparate as cold Siberia, tropical Amazon, and the temperate HKH region (Fig. 8.1).

Forests play a vital role in combating climate change and mitigating its effects. In the Hindu Kush Himalaya (HKH), they are an important source of livelihood for the region’s growing population. With forest degradation and deforestation increasing, it has become all the more necessary to have a reliable climate resilient forest management system. At present, lack of precise information on forest degradation and the impacts of climate change on forest ecosystems hinder the conservation, planning and management of forest ecosystems in Nepal. We attempt to tackle this issue in collaboration with Department of Forests and Soil Conservation (DoFSC), Nepal, by providing scientific and reliable data on vulnerability of forests to anthropogenic factors and climate change using geospatial tools and techniques. We introduced a two-way multitier approach in Nepal to support the identification and implementation of adaptation and management strategies with special focus on forest ecosystems. It aims to reduce the vulnerability of forests to climate change and the degradation of forest ecosystems due to anthropogenic drivers. We used multispectral satellite datasets, data on climate trends and projections, and published data on extraction of forest resources in the study area. We then used data mining to quantify the influence of temperature and precipitation on functioning of forests by using MODIS data of net primary productivity, leaf area index, evapotranspiration and climatic trends and projections data. Finally, we overlayed the forest degradation map on forest climate sensitivity map to identify the hotspots of degradation and sensitivity needing immediate attention. These hotspots are defined as “adaptation footprints”, which help decision makers to prioritize their activities within their district. Most of the forest ecosystems in mid-western and far-western Nepal are highly sensitive to observed and predicted impacts of climate change, which need immediate prioritization and management. The products of this study are accessible through a web-based decision support tool, which will help decision makers at district and province level to prioritize the activities of forest management.

Using a two-color time-resolved pump-probe spectroscopy scheme, we studied the generation and detection of longitudinal coherent acoustic phonons, generated by ultrafast laser pulses in a semiconductor heterostructure. Our structure was a $p$-doped, 100-nm-thick ferromagnetic GaMnAs layer grown on a GaAs substrate. By probing the transient reflectivity in the time domain, we observed a strong dependence of the coherent phonon's amplitude on the external magnetic field. Our theoretical model relates this dependence to the increase in the detectability of coherent phonons in the presence of external magnetic fields. This enhancement comes from the formation of Landau levels in the absorption spectrum and leads to large changes in the real and imaginary parts of the dielectric function with strain. When the probe laser energy is close to an allowed Landau-level transition, the detectability of the coherent phonons can be significantly enhanced. Our results suggest that not only can one increase the detection of coherent phonons with magnetic fields, one can also enhance the generation by tuning the wavelength of the pump laser pulse to coincide with a Landau-level resonance.

Near surface indium arsenide quantum wells have recently attracted a great deal of interest since they can be interfaced epitaxially with superconducting films and have proven to be a robust platform for exploring mesoscopic and topological superconductivity. In this work, we present magnetotransport properties of two-dimensional electron gases confined to an indium arsenide quantum well near the surface. The electron mass extracted from the envelope of the Shubnikov-de Haas oscillations shows an average effective mass $m^{*}$ = 0.04 at low magnetic field. Complementary to our magnetotransport study, we employed cyclotron resonance measurements and extracted the electron effective mass in the ultra high magnetic field regime. Our measurements show that the effective mass depends on magnetic field in this regime. The data can be understood by considering a model that includes non-parabolicity of the indium arsenide conduction bands.

UNSTRUCTURED Since the declaration of Covid-19 as a Pandemic by WHO on 13th March,2020 over 210 countries / territories have active cases and 1/3rd of the world’s population are on complete lockdown or partial restriction. Main route of transmission of Covid-19 is through droplets like most communicable respiratory illnesses followed by infected surfaces. Public measures like wearing masks, social distancing, hand washing and other respiratory hygiene are being followed in unprecedented level and people are tested rapidly if they show symptoms of the disease such as fever, cough, fatigue, myalgia and dyspnea.. These symptoms are similar to other respiratory diseases such as common flu, influenza, pneumonia and Tuberculosis and these preventive measures are also effective in these diseases. In Wuhan, China the lockdown lasted for 76 days and seems to follow similar course in other countries. The air pollution and travel has also decreased which will further decrease transmission of respiratory illnesses. These behavioral changes can get embedded into human cultures as seen in Japan after Spanish flu where people regularly wear masks in winter. This might play a vital role to decrease incidence of other respiratory illnesses like Tb and influenza for which we need to be observant and carry time series analysis of the pre and post pandemic data. With proper strategies this could be utilized as an opportunity to reduce burden of other respiratory communicable disease around the globe.

Global generation of municipal solid waste (MSW) is predicted to reach over 2.2 billion tons/year in 2025. Landfilling and incineration, the two most common conventional techniques for MSW processing, negatively impact public health. This study developed and demonstrated electricity generation by co-gasification of two underutilized resources: MSW and agricultural biomass. A patented design of 60-kW downdraft gasifier and an internal combustion engine with 10 kW generator were used to generate electricity from co-gasification of various ratios of MSW and biomass. The maximum heating values (LHV) of syngas obtained at MSW ratio of 0, 20, and 40 wt.% were 6.91, 7.74, and 6.78 MJ/Nm3, respectively. At all MSW to biomass ratios, the maximum electric load generated was 5 kW, with electrical efficiencies of 22, 20, and 19.5% at MSW ratios of 0, 20, and 40 wt.%, respectively. The engine CO, NOx, SO2, and CO2 emission decreased with increasing load, while HC emission increased with increasing load. CO, NOx, and CO2 emissions decreased, while HC and SO2 emissions increased with increase in MSW ratio. Thus, the co-gasification system provides a basis for future development of small-scale power generation to utilize local wastes.

In this study, municipal solid waste was gasified with switchgrass, i.e., co-gasification, using a commercial-scale downdraft gasifier to produce power. The experiments were performed using a commercial-scale 100 kg/h downdraft gasifier at co-gasification ratios of 0, 20 and 40%. The hot and cold gas efficiencies, syngas compositions, heating value and yield, gasifier temperatures and tar content were measured and analyzed. The results indicate that co-gasification of up to 40% MSW performed satisfactorily. The heating values of syngas were 6.2, 6.5 and 6.7 MJ/Nm3 for co-gasification ratios of 0, 20 and 40%, respectively. The cold and hot gas efficiencies were 60.1, 51.1 and 60.0% and 65.0, 55.2 and 64.4% for co-gasification ratios of 0, 20 and 40%, respectively.

The effect of two-photon absorption (TPA) on all-optical logic operation in quantum-dot semiconductor optical amplifier (QD-SOA) has been carried out. We model the rate equation with the TP...

The overall goal of this study was to scale-up a patented downdraft gasifier system for development of a mobile power plant. A 100 kg/h up-scaled downdraft gasifier system was designed, built and evaluated using switchgrass and eastern redcedar as feedstocks. The effect of equivalence ratio (0.15–0.30) were studied for each of biomass feedstock. Performance parameters, including composition, syngas yield, heating value, tar content, and gasification efficiencies were measured and analyzed. Results showed that biomass type and equivalence ratio have a significant influence on the syngas compositions and calorific value. Maximum gasification efficiencies for switchgrass and redcedar were 64 and 80% at optimal equivalent ratios of 0.22 and 0.24, respectively. Based on syngas quality, the performance of the scaled-up gasifier system was superior to the laboratory-scale reactor.

Climate change, pollution, and energy insecurity are currently critical worldwide problems. To improve worldwide energy security and supply, new policies regarding renewable energy and new infrastructure should be developed. Since 2006, Indonesia’s dependency on oil imports has been increasing significantly. Recent policies on renewable energy have been issued to cope with the issue. This study focuses on describing the feasibility of using biogas for energy production in Indonesia. Biogas contains 50–70% methane and 30–50% carbon dioxide and has a calorific value of 21–24 MJ/Nm 3 . Therefore, it can be potentially altered to contain 97% methane prior to injecting into natural gas networks. The prospective derivation of biogas from cattle, pig, and chicken waste in Indonesia could reach approximately 79 Trillion Watt-hours (TWh). In order to use biogas for power generation, two scenarios were created. The electricity demand, the environmental impact and the reduction of GHG emissions were considered over the next 20 years. The first scenario depended on current energy policy and the second scenario depended on biogas as a substitute for the fossil fuel that is still used for generating power. The carbon dioxide (CO 2 ), carbon monoxide (CO), sulfur dioxide (SO 2 ), nitrogen oxides (NO x ), particulate matter (PM), and volatile organic compounds (VOCs) were estimated for each scenario. A resource analysis of the biogas derived from animal wastes was estimated and the economics of biogas production were described. Finally, the most recent renewable energy policies were described to promote the development of this sector.

The demand for energy is ever increasing since the establishment of human society. In recent years, the demand for energy is steadily increasing due to growth of population and industrial development. As conventional sources of energy are on the verge of extinction and are considered threat to the environment, search for alternative forms of energy is increasing. Biodiesel is one of the sources that can play a pivotal role for future energy, especially in transportation sector, as an alternative to diesel fuel. Jatropha is regarded as one of the best options for biodiesel production in tropical and subtropical developing countries. In terms of fuel properties and emission factors, biodiesel from Jatropha has advantages over conventional diesel. In addition, Jatropha biodiesel when compared with other biodiesel is more environment friendly as there is less emissions of greenhouse gases. A review on performance of Jatropha as a fuel shows that, although emission of NO x is increased from 5.58 to 25.97%, PM is reduced by 50 to 72.73%, CO by 50 to 73%, HC by 45 to 67% and CO 2 by 50 to 80%. However, the future of the Jatropha biodiesel will also depend upon the establishment of low-cost and competent biodiesel production technologies.

The ten-year Maoist insurgency in Nepal ended in 2006 with Comprehensive Peace Accord (CPA). A Truth and Reconciliation Commission (TRC) was established to address the human rights violations including societal impacts which occurred during the insurgency and to bring justice to its victims and perpetrators. Hence, this paper explores the role of the TRC in facilitating and establishing peace by analysing and comparing similar TRCs’ operations in South Africa, Liberia, and Sierra Leone. For this, the study utilizes primary information data collection methods and content analysis to critically examine the role of TRCs in the peace process. It identifies the key achievements of these previous TRCs and recommends ‘6R’ measures to Nepali TRC for justice and peace establishment in Nepal.

After ten years of civil war in Nepal (1996 - 2006) the combatant forces brokered the Comprehensive Peace Accord (CPA). The war had ended but peace was never established and Nepal’s political economy remains weak and barely functioning. The CPA has been inoperative because of power struggles of the numerous parliamentary political parties in the post-insurgency Nepalese Governments. The political parties see no use for the CPA in these power struggles. Their sole and continuing objective is to secure political power. The causes of and the problems created by the civil war have been ignored in the power struggles of the parliamentary parties. The peace process in Nepal is now paralysed. The political parties have ignored, avoided, isolated and derailed the peace building process in Nepal. Hence, this paper analyses the political reality and the paralysed peace process in Nepal. It also examines how the activities of political parties have deliberately failed to bring the process of peace building to Nepal. And finally, it proposes practical peace building measures by which peace building could occur in Nepal which would bypass the power struggles of the political parties in Nepal.

The power production from renewable sources must increase to meet the growing demand of power across the globe on a sustainable basis. Unlike most of gasification works that use high density biomass (e.g. wood chips) to generate a high quality syngas, here we introduce a novel gasification system that can use underutilized low density biomass resources to produce power and electricity with high efficiency yet minimum set-up requirement and low emissions. Switchgrass, one of locally abundant and low density biomass, was used as the biomass feedstock. A unique pilot-scale patented gasifier with a cyclonic combustion chamber having a capacity of 60 kW was used. A commercial natural gas – based, spark-ignition (SI) engine with capacity of 10 kW was modified to measure and control air-fuel ratio and fed with the syngas produced directly from the gasifier. The engine load was regulated by an electric load bank to evaluate the engine operational characteristics. The natural gas was used as the reference feed to evaluate the engine and emissions performance. Gas composition and flowrate, output power, electrical efficiency, and exhaust emissions such as CO 2 , CO, NO x , SO 2 , and hydrocarbons were measured. Net electrical efficiency of 21.3% and specific fuel consumption (SFC) of 1.9 kg/kWh were achieved while producing 5 kW at the maximum load using syngas, while 22.7% of electrical efficiency and 0.3 kg/kWh of SFC were achieved using natural gas at the equivalent load. NO x and HC emission produced from the engine was significantly affected by the gas fed and the load applied. CO 2 emission varied moderately yet significantly with the increasing load, while CO and SO 2 emissions did not strongly influenced by the load variation. NO x emission was 21.5 ppm that complies with the California emission standard limit (25.9 ppm). The study results showed that with minimum set-up, the downdraft gasification system coupled with existing commercial natural gas-based spark-ignited (SI) engine can satisfactorily generate sustainable power supply with high efficiency and minimum emissions to support off-grid power application.

The recent low oil prices tend to render the acceleration of renewable energy (RE) development in the world. Only few sectors of RE can still keep growing with this situation. One of the inexhaustible renewable energy sources in Indonesia is palm trees which produce palm oil that can be further processed into biodiesel that can potentially generate power and electricity as well as promote rural economic development. This paper investigates the use of palm biodiesel in Indonesian power sector, especially in the region of Java, Madura, and Bali (JAMALI). Projection on electricity demand, environmental impact, and emissions reduction over the next 20 years were established into two scenarios. The first situation examines recent energy policy, while the second situation promotes substitution of diesel fuel that is still consumed in the JAMALI power generating system. The effect of palm biodiesel on emissions such as CO2, CO, SO2, NOx, PM, and VOCs were calculated for each scenario. An externality study, resource analysis of palm oil plantations, and the economic feasibility of palm biodiesel were also conducted to accomplish the environmental analysis. The analysis shows the urgency for development of policies that support massive scale of biodiesel production.

Flood inundation maps provide valuable information towards flood risk preparedness, management, communication, response, and mitigation at the time of disaster, and can be developed by harnessing the power of satellite imagery. In the present study, Sentinel-1 Synthetic Aperture RADAR (SAR) data and Otsu method were utilized to map flood inundation areas. Google Earth Engine (GEE) was used for implementing Otsu algorithm and processing Sentinel-1 SAR data. The results were assessed by (i) calculating a confusion matrix; (ii) comparing the submerge water areas of flooded (Aug 2018), non-flooded (Jan 2018) and previous year's flooded season (Aug 2016, Aug 2017), and (iii) analyzing historical rainfall patterns to understand the flood event. The overall accuracy for the Sentinel-1 SAR flood inundation maps of 9th and 21st August 2018 was observed as 94.3% and 94.1% respectively. The submerged area (region under water) classified significant flooding as compared to the non-flooded (January 2018) and previous year's same season (August 2015-2017) classified outputs. Summing up, observations from Sentinel-1 SAR data using Otsu algorithm in GEE can act as a powerful tool for mapping flood inundation areas at the time of disaster, and enhance existing efforts towards saving lives and livelihoods of communities, and safeguarding infrastructure and businesses.

We simulate supercontinuum generation for various shapes of a dispersion varying As2S3 waveguides on MgF2 substrate with air cladding. The supercontinuum generation is simulated for pulses of 2000 W peak power and 50 fs pulse width centered at 1.55 μm wavelength. For a uniform waveguide the generated spectrum is considerably narrower than that for a non-uniform waveguide. This is because the non-uniform waveguide allows a continuous phase matching of the generated waves through nonlinear interaction. We have demonstrated that a high coefficient of nonlinear refractive index is necessary for generating supercontinuum with large bandwidths. Larger supercontinuum bandwidth is predicted for waveguides with increasing As2S3 thickness along the propagation direction.

A scheme to generate 50 GHz pulse train using rational harmonic mode locking technique is proposed and studied experimentally. The modulation frequency is adjusted to achieve a 50 GHz pulse train which has a pulse width of 5.25 ps. Numerical simulation results show good agreement with the experimental results.

The effect of two-photon absorption (TPA) on all-optical logic operation in quantum-dot semiconductor optical amplifier (QD-SOA) has been carried out. The rate equation was modeled with the TPA effect for the logic XOR gate, AND gate, and, for pseudo-random bit sequence (PRBS) generation. The output Q-factor (quality) has increased due to the implementation of TPA induced pumping. The results show that the quality of the output depends on the input pulse width and the speed of operation. The PRBS system has been shown to operate at 250 Gb/s and 320 Gb/s and the Q-factor decreases with an increase in pulse width.

Invasive alien plant species (IAPS) can pose severe threats to biodiversity and stability of native ecosystems, therefore, predicting the distribution of the IAPS plays a crucial role in effective planning and management of ecosystems. In the present study, we use Maximum Entropy (MaxEnt) modelling approach to predict the potential of distribution of eleven IAPS under future climatic conditions under RCP 2.6 and RCP 8.5 in part of Kailash sacred landscape region in Western Himalaya. Based on the model predictions, distribution of most of these invasive plants is expected to expand under future climatic scenarios, which might pose a serious threat to the native ecosystems through competition for resources in the study area. Native scrublands and subtropical needle-leaved forests will be the most affected ecosystems by the expansion of these IAPS. The present study is first of its kind in the Kailash Sacred Landscape in the field of invasive plants and the predictions of potential distribution under future climatic conditions from our study could help decision makers in planning and managing these forest ecosystems effectively.

The pretreatment of plant biomass negatively impacts the economics of many bioenergy and bioproduct processes due to the thermochemical requirements for deconstruction of lignocelluluose. An effective strategy to reduce these severity requirements is to pretreat the biomass with white-rot fungi, such as Trametes versicolor, which have the innate ability to deconstruct lignocellulose with a suite of specialized enzymes. In the present study, the effects of 12 weeks of pretreatment with a wild-type strain (52J) and a cellobiose dehydrogenase-deficient strain (m4D) of T. versicolor on hardwood and Miscanthus were explored. Both strains of T. versicolor led to significant decreases of insoluble lignin and significant increases of soluble lignin after acid hydrolysis, which suggests improved lignin extractability. The glucose yields after saccharification using an enzyme cocktail containing chitinase were similar or significantly higher with 52J-treated biomass compared to untreated hardwood and Miscanthus, respectively. The fungal treated biomass, regardless of the strain used, also showed significant increases in energy content and compressive strength of pellets. Overall, the use of T. versicolor as a pretreatment agent for hardwood and Miscanthus could be an environmentally friendly strategy for conversion technologies that require delignification and saccharification, and/or processes that require densification and transport.

Purpose Lignocellulosic biomass has been regarded as an important future energy source due to its excessive availability; however, the wide application of this material for many applications is restricted by the high costs associated with densification, transportation, thermo-chemical pretreatment and conversion. In order to increase the density of lignocellulosic biomass, it is typically compressed into pellets or briquettes. This frequently requires the addition of additives, which may negatively impact the economics of the process. Environmentally-friendly binding agents that can be obtained inexpensively are therefore desirable. This study examines the change in physicochemical properties of densified Miscanthus straw where algae were used as a binding agent.

Globally threatened Red Panda is found in isolated high mountain’s bamboo- forest patches in Nepal, India, Bhutan, China and Burma. This study was focused in Gaurishankar Conservation Area, one of the newly declared protected areas of Nepal, with aim to glean baseline information regarding existence of Red Panda, its habitat status and conservation issues. Methods like altitudinal line intercept, key informant survey and consultation (with local people, herders, conservation stakeholder) were used to address the objectives. Marbu, Kalinchok, Gaurishankar (Dolkha District), Chuchure, Gumdel (Ramechhap District) and Fulpingkatti (Sindupalchok District) area were surveyed in first phase of study and presence of Red Panda distribution was recorded from Marbu, Kalinchok, Chuchure and Fulpingkatti forests areas through sign evidence (fecal pellets). A total of 24 transects were established randomly in the whole area and only 16 transects were worked effectively because of topographical barrier. Distribution of Red Panda was found as clumped pattern ( ). Among these sites, frequent sign encounter was recorded in Marbu (5.45/km) area followed by Fulpingkatti (5.06/km), Kalinchok (3.73/km) and Chuchre (1.67/km). Like in other areas, conservation issues like habitat destruction, livestock pressure, fire wood collection and illegal poaching were rampant in Gaurishankar also. This study recommended for detail survey on population status and conservation activities should be elaborated in current identified habitat as well as further survey should be focused on other possible habitats within conservation area. DOI: http://dx.doi.org/10.3126/init.v5i0.10252 The Initiation 2013 Vol.5; 43-49

We perform a magneto-infrared spectroscopy study of the semiconductor to semimetal transition of InAs/GaSb double quantum wells from the normal to the inverted state. We show that owing to the low carrier density of our samples (approaching the intrinsic limit), the magneto-absorption spectra evolve from a single cyclotron resonance peak in the normal state to multiple absorption peaks in the inverted state with distinct magnetic field dependence. Using an eight-band Pidgeon-Brown model, we explain all the major absorption peaks observed in our experiment. We demonstrate that the semiconductor to semimetal transition can be realized by manipulating the quantum confinement, the strain, and the magnetic field. Our work paves the way for band engineering of optimal InAs/GaSb structures for realizing novel topological states as well as for device applications in the terahertz regime., Comment: 15 pages, 9 figures

Myeloid Sarcoma (MS) is a tumour mass of myeloblasts or immature myeloid cells in an extra-medullary site. Isolated MS is a red disease found only seen in case reports. Here, we present the case of a 25years old man with bilateral cervical lymphadenopathy who was diagnosed as MS on the basis of lymph node biopsy and immunohistochemistry. There is no definite consensus on management of MS and needs prospective trials. DOI: http://dx.doi.org/10.3126/jcmc.v4i3.11941Journal of Chitwan Medical College 2014; 4(3):46-48

In this paper, we propose and experimentally demonstrate a mode locked fiber ring laser with the implementation of a photonic crystal fiber (PCF) to generate pulse train at high speed. This fiber ring laser combines rational harmonic mode locking based on a Lithium Niobate Mach-Zehnder modulator and nonlinear polarization rotation from a highly nonlinear PCF. By fine tuning of the modulation frequency and the polarization controllers in the cavity, a 30 GHz pulse train with pulse width 1.9 ps is generated. Without the PCF, the pulse width at 30 GHz from the rational harmonic mode locking is 5.8 ps. We also conduct numerical simulations of the pulse evolution, which shows good agreements of the experimental results.