Although suicide attacks started to be systematically used by terrorist organizations in the 1980s, there has been a noticeable increase in these attacks in the 2000s. According to __31__, a total of 4,814 suicide attacks took place in over 40 countries from 1982 to September 2015.

    2015 __32__ record numbers in respect of suicide attacks. While such attacks took place only in one country in 1981, 21 countries were hit by the suicide attacks in 2015: It has been reported that 9,109 civilians were killed or injured by suicide attacks in 248 separate incidents in the same year. These civilian losses __33__ about 86 percent of the total losses caused by suicide attacks. The total number of civilians killed or injured as the result of suicide attacks in 2015 has increased 78 percent when __34__ that of 2011. Again in this year, the number of the civilians that died or were injured as a result of suicide attacks is more than half (56 percent) of those who've been killed or injured by firearms, bombs or explosives worldwide.

    With a growing trend in 2016, the number of suicide attacks has __35__ in the last days of March to an extent that almost every day at least one suicide attack took place. Reports about suicide attacks came from Belgium, Turkey, Iraq, Pakistan, Yemen, Nigeria __36__ leaving behind hundreds of people brutally murdered and injured and far too many more in shock, horror and panic. The intelligence reports state that the attacks expected to take place in the coming days might be of a more extensive and __37__ nature.

    As could be seen, as the extent of the massacres carried out in the Islamic world — without making any distinction between civilians and terrorists — increases __38__ the "Fight against Terror," the ferocity and the dimensions of the terror generated by this violence increases as well. The delusion of the "Fight against Terror," which is dragging almost the whole world behind it today, has done precious little but promote the ideology of terrorist and extremist groups more than ever in the history of the world. It is not eliminating terrorism; the "Fight against Terrorism" is __39__ spreading it. The cities and regions destroyed by air __40__ and military interventions have turned into training centers for all kinds of potential terrorists, human bombs and suicide bombers.

(AB) constituted (AC) smoothly (AD) temperate (AE) escalated (BC) operations (BD) in the name of (BE) successively (CD) statistics (CE) inadvertently (DE) packed with (ABC) transport (ABD) compared to (ABE) undertook (BCD) saw (BCE) horrific

    They lie buried- their long, tentaclelike arms outstretched—in all the tissues of our bodies that interact with the environment. In the lining of our nose and lungs, lest we inhale the influenza virus in a crowded subway car. In our gastrointestinal tract, to alert our immune system if we swallow a dose of salmonella bacteria. And most importantly, in our skin, they lie in wait as stealthy sentinels should microbes breach the leathery fortress of our epidermis.

    They are dendritic cells, a class of white blood cells that encompasses some of the least understood but most fascinating actors in the immune system. Over the past several years, researchers have begun to unravel the mysteries of how dendritic cells educate the immune system about what belongs in the body and what is foreign and potentially dangerous. Intriguingly, they have found that dendritic cells initiate and control the overall immune response. For instance, the cells are crucial for establishing immunological “memory,” which is the basis of all vaccines. Indeed, physicians, including those at a number of biotechnology companies, are taking advantage of the role that dendritic cells play in immunization by “vaccinating” cancer patients with dendritic cells loaded with bits of their own tumors to activate their immune system against their cancer. Dendritic cells are also responsible for the phenomenon of immune tolerance, the process through which the immune system learns not to attack other components of the body.

    Dendritic cells are relatively scarce: they constitute only 0.2 percent of white blood cells in the blood and are present in even smaller proportions in tissues such as skin. In part because of their rarity, their true function eluded scientists for nearly a century after they were first identified in 1868 by German anatomist Paul Langerhans, who mistook them for nerve endings in the skin.

    In 1973 Ralph M. Steinman of the Rockefeller University rediscovered the cells in mouse spleens and recognized that they are part of the immune system. The cells were unusually potent in stimulating immunity in experimental animals. He renamed the cells “dendritic” because of their spiky arms, or dendrites, although the subset of dendritic cells that occur in the epidermis layer of the skin are still commonly called Langerhans cells.

    There are several subsets of dendritic cells, which arise from precursors that circulate in the blood and then take up residence in immature form in the skin, mucous membranes, and organs such as the lungs and spleen. Immature dendritic cells are endowed with a wealth of mechanisms for capturing invading microbes: they reel in invaders using suction cup-like receptors on their surfaces, they take microscopic sips of the fluid surround them, and they suck in viruses or bacteria by engulfing them in sacks known as vacuoles. Once they devour foreign objects, the immature cells chop them into fragments (antigens) that can be recognized by the rest of the immune system.

    Dendritic cells are very efficient at capturing and presenting antigens: they can pick up antigens that occur in only minute concentrations. As they process antigens for presentation, they travel to the spleen through the blood or to lymph nodes through a clear fluid known as lymph. Once at their destinations, the cells complete their maturation and present their antigen-laden molecules to naïve helper T cells, those that have never encountered antigens before. Dendritic cells are the only cells that can educate naïve helper T cells to recognize an antigen as foreign or dangerous. This unique ability appears to derive from costimulatory molecules on their surfaces that can bind to corresponding receptors on the T cells.

    Once educated, the helper T cells go on to prompt so-called B cells to produce antibodies that bind to and inactivate the antigen. The dendritic cells and helper cells also activate killer T cells, which can destroy cells infected by microbes. Some of the cells that have been educated by dendritic cells become “memory” cells that remain in the body for years—to combat the invader in case it ever returns.

    Activating naive helper T cells is the basis of vaccines for everything from pneumonia to tetanus to influenza. Scientists are now turning the new knowledge of the role that dendritic cells play in immunity against microbes and their toxins into a strategy to fight cancer.

    Cancer cells are abnormal and as such are thought to generate molecules that healthy cells don’t. If researchers could devise drugs and vaccines that exclusively targeted those aberrant molecules, they could combat cancer more effectively while leaving normal cells and tissues alone—thereby eliminating some of the pernicious side effects of chemotherapy and radiation, such as hair loss, nausea and weakening of the immune system caused by destruction of the bone marrow.

    Such trials generally employ vaccines made of dendritic cells precursors that have been isolated from cancer patients and grown in the laboratory together with tumor antigens. During this process, the dendritic cells pick up the antigens, chop them up and present them on their surfaces. When injected back into the patients, the antigen-loaded dendritic cells are expected to ramp up patients’ immune response against their own tumors.

     Several researchers fear that such vaccines might induce patients’ immune systems to attack healthy tissue by mistake. In addition, tailoring a dendritic cell vaccine to fight a particular patient’s tumors might not be economically feasible. But many scientists are working to circumvent the costly and time-consuming steps of isolating cells from patients and manipulating them in the laboratory for reinjection.

    As we learn more about the molecules that control dendritic cells, we will find ways to harness their therapeutic potential. The increasing number of scientists and corporations working on dendritic cells portends that we will soon be able to maximize the biological power of these cells to treat and prevent the diseases that plague humankind.

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       The world is experiencing a profound demographic shift, characterized by a rapidly aging population. This phenomenon, often referred to as an aging society, presents unique challenges and implications for individuals, communities, and governments. One of the key challenges posed by an aging society is the strain it puts on healthcare systems. As people age, they tend to require more medical care, including specialized services for agerelated illnesses and conditions. This increased demand for healthcare services can lead to resource shortages, longer waiting time, and escalating healthcare costs.

        Another significant implication of an aging society is the strain on social welfare systems. With a larger proportion of the population entering retirement age, there is an increased demand for pension benefits, social security, and elder care services. The sustainability of these systems becomes a pressing concern, as the shrinking working-age population may need help to support the growing number of retirees. Additionally, an aging society brings about changes in family dynamics and caregiving responsibilities. As older adults may require assistance with daily activities and healthcare management, the burden often falls on family members, predominantly women, who may have to juggle work, personal life, and caregiving duties. This can lead to increased stress and financial strain on families, as well as potential conflicts and reduced quality of life for both caregivers and the elderly.

       Furthermore, an aging society can have economic repercussions. The labor force may experience a decline in productivity and potential labor shortages as a result of a shrinking working-age population. This can hamper economic growth, increase dependency ratios, and put pressure on social security systems. Governments and businesses need to adapt by implementing strategies to support older workers, promote workforce participation, and address skills gaps. Despite the challenges, an aging society also presents opportunities. Older adults have a wealth of knowledge, skills, and experience that can contribute to society in various ways. They can engage in volunteer work, mentor younger generations, and participate in lifelong learning programs. Creating age-friendly environments and promoting active aging can harness the potential of older adults, fostering social integration and intergenerational cohesion.