An Analysis of Liberia’s Vulnerability to Climate Change in the Context of Least Developed Countries (LDCs): A Review

Climate change is an alarming global challenge, particularly affecting the least developed countries (LDCs) including Liberia. These countries, located in regions prone to unpredictable temperature and precipitation changes, are facing significant challenges, particularly in climate-sensitive sectors such as mining and agriculture. LDCs need more resilience to adverse climate shocks but have limited capacity for adaptation compared to other developed and developing nations. This paper examines Liberia’s susceptibility to climate change as a least developed country, focusing on its exposure, sensitivity, and adaptive capacity. It provides an overview of LDCs and outlines the global distribution of carbon dioxide emissions. The paper also evaluates specific challenges that amplify Liberia’s vulnerability and constrain sustainable adaptation, providing insight into climate change’s existing and potential effects. The paper emphasizes the urgency of addressing climate impacts on Liberia and calls for concerted local and international efforts for effective and sustainable mitigation efforts. It provides recommendations for policy decisions and calls for further research on climate change mitigation and adaptation.

The Implications of Urbanization Processes in Developed Countries for Africa

Urbanization is the inevitable path of national economic development,and the level of urbanization development in most African countries is still low.By analyzing five typical developed countries in the United States,Britain,France,Germany,and Japan,this paper discusses the promoting factors and problems of the rapid urbanization development in their specific years,as well as the experiences and lessons that Africa can learn,so as to prevent Africa from taking the detour in the urbanization process of Western developed countries and promote the balanced regional development of various African countries.

New aspects of a small GTPase RAB35 in brain development and function

In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting the cargo of proteins,lipids,and other molecules to appropriate compartments via transport vesicles or intermediates.These processes are strictly regulated by various small GTPases such as the RAS-like in rat brain(RAB)protein family,which is the largest subfamily of the RAS superfamily.Dysfunction of membrane trafficking affects tissue homeostasis and leads to a wide range of diseases,including neurological disorders and neurodegenerative diseases.Therefore,it is important to understand the physiological and pathological roles of RAB proteins in brain function.RAB35,a member of the RAB family,is an evolutionarily conserved protein in metazoans.A wide range of studies using cultured mammalian cells and model organisms have revealed that RAB35 mediates various processes such as cytokinesis,endocytic recycling,actin bundling,and cell migration.RAB35 is also involved in neurite outgrowth and turnover of synaptic vesicles.We generated brain-specific Rab35 knockout mice to study the physiological roles of RAB35 in brain development and function.These mice exhibited defects in anxiety-related behaviors and spatial memory.Strikingly,RAB35 is required for the precise positioning of pyramidal neurons during hippocampal development,and thereby for normal hippocampal lamination.In contrast,layer formation in the cerebral cortex occurred superficially,even in the absence of RAB35,suggesting a predominant role for RAB35 in hippocampal development rather than in cerebral cortex development.Recent studies have suggested an association between RAB35 and neurodegenerative diseases,including Parkinson's disease and Alzheimer's disease.In this review,we provide an overview of the current understanding of subcellular functions of RAB35.We also provide insights into the physiological role of RAB35 in mammalian brain development and function,and discuss the involvement of RAB35 dysfunction in neurodegenerative diseases.

Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins

Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies.

Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development

The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation.

Construction controlling and strength increasing characteristics of locally developed epoxy asphalt mixture

The construction controlling elements,including construction performance at low ambient temperatures,reserved time ranges,and the strength increasing rule,for locally developed epoxy asphalt mixture（LDEAM） are studied through laboratory tests.Air void and Marshall stability are chosen as the performance measures for evaluating the construction quality.The wheel rolling test is used to simulate the actual construction situations,while the Marshall test and the Brookfield viscosity test are adopted to study the strength increasing rule.The experimental results reveal that the LDEAM can be constructed under a low ambient temperature condition of 10℃,and its longest reserved time is 70 min at a reserved temperature of 120℃.Test also shows that the strength of the LDEAM increases with time and temperature before cured.Finally,the theoretical reason for the strength increasing rule is analyzed on the basis of the organic chemistry theory.

SWOT Analysis of Tourist Resources in Underdeveloped Counties—With Pingle County in Guilin City as the Study Case

Strengths,weaknesses,opportunities and threats of tourism development in Pingle County were analyzed to give a pertinent guide for its under developed tourism industry and economy,moreover,suggestions were proposed for the further development of local tourist resources.

Displacive transformation as pathway to prevent micro-cracks induced by thermal stress in additively manufactured strong and ductile high-entropy alloys

The micro-cracking behaviors of two high-entropy alloys(HEAs) of the FeMnCoCrNi family prepared by selective laser melting were systematically studied. Residual stresses were also analyzed by X-ray diffraction technique. Results show that the equiatomic FeMnCoCrNi HEAs with a relatively stable single-phase face-centered cubic(FCC) structure suffered from micro-cracking with residual tensile stress after laser melting. In contrast, the metastable non-equiatomic Fe MnCoCr HEAs with reduced stacking fault energy are free of micro-cracks with residual compressive stress at various volumetric energy densities(VEDs). The displacive transformation from the FCC matrix to the hexagonal close-packed(HCP) phase during cooling prevents the micro-cracking via consuming thermal stress related internal energy. Further, the displacive transformation during tensile deformation contributes to the higher strength and ductility of the metastable dual-phase HEA compared to that of the stable single-phase HEA. These findings provide useful guidance for the design of strong, ductile, and crack-free alloys for additive manufacturing by tuning phase stability.

Countermeasures and Investigation of Land Circulation in Less Developed Agricultural Area of Henan Province,China

Some places in Henan Province are investigated by using sample surveys and interviews. Result shows that land circulation in less developed agricultural area of Henan Province has the characteristics of small scale,single form,short period,and circulation land in economic core region. Problems in land circulation are as follows:slow transfer of rural surplus labor force,hard implementation of fundamental land circulation,complicated mentality towards rural land circulation,many misgivings about land circulation,the unformed social service system of land circulation,and imperfect agricultural risk prevention mechanism for circulated land use. Based on the characteristics of land circulation,suggestions for promoting the land circulation of less developed agricultural areas are put forward in order to solve the problems in land circulation and to lay the foundation for effective implementation of land circulation,such as speeding up the development of urbanization,developing the circulation of collective land,effectively implementing the laws and regulations of rural collective land circulation,transferring land according to law,establishing market mechanism of agricultural land circulation,promoting the agricultural industrialization,establishing market mechanism of agricultural land circulation,promoting the agricultural industrialization,energetically readjusting rural industrial structure,and developing economy with local characteristics.

STUDY ON FUNCTION OF COMPONENTS OF DY NAMIC SYSTEM OF TOURISM DEVELOPMENT IN DEVELOPED REGION---A Case Study of Foshan in Guangdong Province

In the forming of the Dynamic System of Tourism Development (DSTD)in developed regions from the view of supply side,the Delphi Method and the Analytical Hierarchy Process(AHP)are used to count the weight of each component of the DSTD.It has been fou nd that the attraction subsystem is t he most important one of the three subsystems at the first hierarchical level of DSTD,which means that tourist attractions are always the principal factors for regional tourism development,even in develo ped regions.But it is also noteworth y that the significance of the attraction subsystem is not dominant in the DSTD.At the sec ond hierarchical level,the physica l attraction subsystem rank No.1,while the weight of the non-physical attraction subsystem is just a little larger t han the weight of the hardware subsystem and that of software subsystem.And the weights of the three components in the medium subsystem are similar.The top 3factors at the third hierarchical level are scenic spot,location and regional econ omic impact.The result verifies the conclusions of qualitative analysis,which depends on the market research and the study of historical date,that the most imp ortant compo-nent of the DSTD in Foshan is the impact of the developed economy.Knowing t he weight of each component of the DST D can be helpful to make out the most use ful force,furthermore to determine the future orientation for regional tourismdevelop-ment.

Development Paths of Characteristic Towns in Underdeveloped Areas in Central China——A Case Study of Yichun,Jiangxi

The demonstration effect triggered by the construction of Zhejiang's characteristic towns has attracted attention and learning from all over the country,and has set off a boom in building characteristic towns across the country. Under the dual constraints of industrial development and resource intensive use,the undeveloped areas of central China must find suitable development paths for characteristic towns. Taking Yichun City as an example,this article analyzes the advantages of Yichun City for developing characteristic towns combining its natural and economic conditions. In addition,the characteristic town development paths,such as vigorously promoting the construction of urban facilities,highlighting the characteristics relying on existing small towns,constructing an industrial chain of " ecology + leisure",highlighting cultural charm,and improving development grade,are proposed to provide useful reference for the development of characteristic towns in this type of underdeveloped cities in central China.

Empirical Study on Factors Influencing Farmland Circulation in Economically Developed Areas

Farmland circulation is the foundation of development of regional farmland market.With the aid of survey data of Jiangsu Province and using Heckman two-stage method,this paper analyzed factors influencing farmland circulation from supply and demand of land.Results showed that non-agricultural employment,social security level,and regional economic development level are key factors.In view of these factors,it is recommended to improve rural labor quality,establish perfect rural social security system,and constantly improve rural security level,which are fundamental ways to promoting farmland circulation and improve circulation market.

COMPARISON OF THE STRUCTURAL CHARACTERISTICS OF DEVELOPED VERSUS UNDEVELOPED MID-LEVEL VORTEXES

Using the NCEP 1°×1°reanalysis data,several obvious differences of the structural characteristics of developed versus undeveloped mid-level vortexes are studied.First,the central vorticity of the developed mid-level vortex increases towards higher levels while the undeveloped one decreases.The low-level convergence structure maintains well in the developed mid-level vortex whereas the undeveloped one does badly.Second,on the one hand,according to the symmetric analysis,the horizontal wind field and wind vertical section of the developed mid-level vortex are well symmetric while those of the undeveloped one are less symmetric.Meanwhile,weak wind vertical shear help the developed mid-level vortex to establish a warm core in upper-and mid-levels of the troposphere.On the other hand,according to the balance analysis,better balance between wind and pressure is shown in the mid-and lower-levels of the troposphere of the developed mid-level vortex than in those of the undeveloped vortex.Third,positive anomaly of potential vorticity is enhanced and developed in the vertical direction of the developed vortex.However,the undeveloped vortex weakens with a weak positive anomaly.

Women’s Awareness and Attitudes towards Labor Analgesia Influencing Practice between Developed and Developing Countries

Childbirth experience is one of the most intense pain that majority of women will endure during their lifetime. Concerns about pain in labor remain a hot topic, and its popularity gets more common day by day as more women become aware of their rights to achieve a better quality of care during labor. There are various non-pharmacologic (transcutaneous electrical nerve stimulation, hydrotherapy, intradermal water injections and acupuncture) and pharmacologic treatments (nitrous oxide, opioids and regional analgesia techniques: spinal, epidural and combined epidural analgesia) available today. Among these, epidural analgesia offers the most effective form of pain relief and is considered to be the gold standard of labor analgesia. Despite having labor analgesic services, most women still go through painful labor due to lack of knowledge regarding it, particularly in developing countries. The main source of information regarding pain reliefs is from friends and relatives, revealing the lack of information from caregiver’s side. So this study reflects that there is a wide gap in the communication between pregnant women and obstetricians. It supports the fact that obstetricians through the practice of routinely offering labor analgesia can significantly improve the maternal and perinatal outcomes of pregnancy. Provision of standardized epidural analgesia information at an appropriate time in their pregnancy may benefit them by the practice of mutual decision-making. Thus, it may prevent women from making a difficult choice of cesarean section to avoid the fear of painful labor.

Image Preprocessing Methods to Identify Micro-cracks of Road Pavement

Standards of highway conservation and maintenance are improved gradually following the improvement of requirements of road service. Before obvious damage such as obvious cracking (block,transverse, longitudinal ) and rutting emerge, inconspicuous distress (micro-cracks, polishing, pockmarked) is generated previously. These inconspicuous distresses may provide basis and criteria for pavement preventive maintenance. Currently most of preventive conservation measures are determined by experienced experts in maintenance and repair of road after site visits. Thus method is difficult in operation, and has a certain amount of instability as it is based on experience and personal knowledge. In this paper, camera and laser were used for automated high-speed acquisition images. Methods to preprocess pavement image are compared. The pretreatment method suitable for analyze micro-cracks picture is elected, an effective way to remove shadow is also proposed.

A presumed iridocyclitis developed to panophthalmitis caused by a non-metallic intraocular foreign body

Dear Editor,I write to present one case report of a patient suffered the panophthalmitis caused by non-metallic foreign body with no etiologic agent and recovered quickly by phacoemulsification and vitrectomy with silicone oil tamponade.Ocular trauma remains a major cause of blindness, particularly in the working-age population.

Optimization and Regulation Policy for Land Use Changes Based on Low-carbon Emission in Developed Regions of China

Land use and cover change(LUCC) is one of the important causes of the Earth’s carbon cycle imbalances resulting from failure in optimizing land use. The solution to this problem has been the hotspot of research in land and environmental science. We took 'low carbon', 'energy saving' and 'high-efficiency' as the goals of land use optimization,and integrated Markov-CA(Cellular Automaton),the Grid-Fractal model and GIS,in order to study carbon emission objective function,to establish a simulation method for land use spatial allocation optimization,to evaluate the effect of the method on carbon emissions. Regulation policy on three types of land use spatial allocation was proposed,including 'low-carbon type', 'low-carbon-economic type' and 'economic type'. We applied the method to analyze the land use spatial allocation in Taixing City of the 'Yangtze River Delta' regions in China,and obtained the following results:(i) The three optimization types would improve carbon emissions by 3. 21%,1. 80% and 0. 36% respectively in 2020,compared with 2010;(ii) The actual planning for 2020 was close to the 'low-carbon-economic type';(iii) The optimization method and regulation policy,combining local optimization and global control,could meet the sustainable multi-objective requirements for low-carbon constraints of land use spatial allocation. The result of this research could also serve as a reference for exploration into patterns of regional low-carbon land use and measures for energy saving and emission reduction.

Institutions and FDI:evidence from developed and developing countries

This study investigates the impact of institutional quality on Foreign Direct Investment(FDI)inflows using panel data for low,lower-middle,upper-middle and high-income countries for the sample period of 1996-2016 using the system Generalized Method of Moments(GMM).The empirical results confirm that institutional quality has a positive impact on FDI in all group of countries.The magnitude of the coefficients of control of corruption,government effectiveness,political stability,regulatory quality,rule of law,and voice and accountability for FDI inflows are greater in developed countries than in developing countries.We conclude that institutional quality is a more important determinant of FDI in developed countries than in developed countries.However,GDP per capita,agriculture value-added as a percentage of GDP,and inflation influence FDI inflows negatively in developed countries,while GDP per capita,trade openness,agriculture value-added as a percentage of GDP,and infrastructure have positive and statistically significant impacts on FDI inflows in developing countries.Trade openness as a percentage of GDP and infrastructure positively affect FDI in developed countries.From our analysis,we infer that institutional quality is a more important determinant of FDI in developed countries than in developing countries.

A Single-Frequency Linearly Polarized Fiber Laser Using a Newly Developed Heavily Tm3+-Doped Germanate Glass Fiber at 1.95 μm

A compact linearly polarized, low-noise, narrow-linewidth, single-frequency fiber laser at 1950nm is demonstrated. This compact fiber laser is based on a 21-mm-long homemade Tm3＋-doped germanate glass fiber. Over 100-mW stable continuous-wave single transverse and longitudinal mode lasing at 195Ohm are achieved. The measured relative intensity noise is less than -135dB/Hz at frequencies over 5 MHz. The signal-to-noise ratio of the laser is larger than 72dB, and the laser linewidth is less than 6kHz, while the obtained linear polarization extinction ratio is higher than 22 dB.

Challenges Brought about by Rapid Changes in Chinese Diets: Comparison with Developed Countries and Implications for Further Improvement

Given developments in urbanization, agricultural, and technological practices, the diet and lifestyle of developed countries has changed dramatically over the course of the last century[1].