The legacy of United States cluster munition use in Laos and Cambodia during the Second Indochina War is residual bomblets that unexpectedly detonate years later, killing and injuring children, farmers, and other civi...The legacy of United States cluster munition use in Laos and Cambodia during the Second Indochina War is residual bomblets that unexpectedly detonate years later, killing and injuring children, farmers, and other civilians. Cluster munitions release dozens of smaller bomblets that rain deadly ammunition on troops, armored tanks, and vegetation, effectively striking broad sections of war zone landscapes in one launch. While many bomblets detonate immediately, others fail to detonate and can lie dormant on the ground for years. The primary objectives of this study were to document the long-term consequences and impacts of the US Air Force bombing of Laos and Cambodia during the Second Indochina War (1959 to 1973). The historical lessons learned by United States should be shared with Russia and Ukraine governments and military. These countries need to discontinue the use of cluster bombs to prevent additional people living along the Russia-Ukraine border from having to live and die with the consequences of unexploded ordnance, including cluster bombs, for the next century.展开更多
Bomb cyclones are rapidly deepening extratropical cyclones predominantly found in midlatitude regions.These extreme events are particularly frequent over the North Pacific(NP),posing significant societal and environme...Bomb cyclones are rapidly deepening extratropical cyclones predominantly found in midlatitude regions.These extreme events are particularly frequent over the North Pacific(NP),posing significant societal and environmental risks.Currently,our understanding of the variability of bomb cyclones over the NP remains limited.This study analyzes the variations in multiple NP bomb cyclone characteristics from 1980 onward using four major reanalysis datasets.The results show a weakening trend of bomb cyclones since the beginning of the 21st century,which is characterized by significant reductions in maximum near-surface wind speeds,increases in minimum sea level pressure,and slower deepening rates.Further analysis reveals that the observed weakening trend of bomb cyclones is closely linked to a reduction in maximum 850 hPa Eady growth rate,driven primarily by reduced vertical wind shear within the 30°-45°N latitudinal band.Furthermore,our findings indicate that the Aleutian Low acts to modulate the meridional air temperature gradient over the midlatitude NP,which is corroborated by climate model outputs.This modulation provides a pathway for the Aleutian Low to affect low-level baroclinicity and thus bomb cyclone characteristics.These results have important implications for future projections of bomb cyclone activity over the NP,aiding in risk assessment and mitigating the impacts of these extreme events.展开更多
Lung cancer is one of the most common malignant tumors with the fastest increase in the incidence rate and mortality.Even after maximum tumor resection assistance with a radiotherapy and chemotherapy combination,the r...Lung cancer is one of the most common malignant tumors with the fastest increase in the incidence rate and mortality.Even after maximum tumor resection assistance with a radiotherapy and chemotherapy combination,the recurrence of non-small cell lung cancer is still inevitable.In addition,low targeting efficiency and poor permeability of drug delivery systems strongly affect the therapeutic efficiency of anti-cancer drugs on non-small cell lung cancer.Here we designed a gemcitabine(GEM)loaded arginineglycine-aspartic acid-cysteine(RGDc)-modified gold mineralization“hybrid nanozyme bomb”(RGTG)to overcome those obstacles.RGDc modification improved the active targeting of liposomes to the tumor tissues with the second near-infrared(NIR-Ⅱ)-triggered gold-shell disruption and GEM release.The collapsed gold-shell particles with a smaller size could penetrate the tumor solid barrier and act as photothermal therapy(PTT)agents to improve PTT therapy and starvation therapy via generating gluconic acid and reactive oxygen species(ROS).Moreover,the resting reversal effect of gold particles on tumor fibroblasts can achieve accelerating tumor penetration of gold particles and GEM.Compared to monotherapy,RGTG showed significant improvement in tumor inhibition,with a tumor volume reduction of 83%compared to the control group,which provides a promising tumor treatment platform for non-small cell lung cancer(NSCLC).展开更多
The laser-guided bomb(LGB)is an air-to-ground pre-cision-guided weapon that offers high hit rates,great power,and ease of use.LGBs are guided by semi-active laser ground-seek-ing technology,which means that atmospheri...The laser-guided bomb(LGB)is an air-to-ground pre-cision-guided weapon that offers high hit rates,great power,and ease of use.LGBs are guided by semi-active laser ground-seek-ing technology,which means that atmospheric conditions can affect their accuracy.The spatial release region(SRR)of LGBs is difficult to calculate precisely,especially when there is a poor field of view.This can result in a lower real hit probability.To increase the hit probability of LGBs in tough atmospheric situa-tions,a novel method for calculating the SRR has been pro-posed.This method is based on the transmittance model of the 1.06μm laser in atmospheric species and the laser diffuse reflection model of the target surface to determine the capture target time of the laser seeker.Then,it calculates the boundary ballistic space starting position by ballistic model and gets the spatial scope of the spatial release region.This method can determine the release region of LGBs based on flight test data such as instantaneous velocity,altitude,off-axis angle,and atmospheric visibility.By more effectively employing aircraft release conditions,atmospheric visibility and other factors,the SRR calculation method can improve LGB hit probabi-lity by 9.2%.展开更多
BACKGROUND: Bombing is a unique incident which produces unique patterns, multiple and occult injuries. Death often is a result of combined blast, ballistic and thermal effect injuries. Various natures of injury, self ...BACKGROUND: Bombing is a unique incident which produces unique patterns, multiple and occult injuries. Death often is a result of combined blast, ballistic and thermal effect injuries. Various natures of injury, self referrals and arrival by private transportation may lead to "wrong triage" in the emergency department. In India there has been an increase in incidence of bombing in the last 15 years. There is no documented triage tool from the National Disaster Management Authority of India for Bombings. We have tried to develop an ideal bombing specific triage tool which will guide the right patients to the right place at the right time and save more lives.METHODS: There are three methods of studying the triage tool: 1) real disaster; 2) mock drill; 3) table top exercise. In this study, a table top exercise method was selected. There are two groups, each consisting of an emergency physician, a nurse and a paramedic.RESULTS: By using the proportion test, we found that correct triaging was significantly different(P=0.005) in proportion between the two groups: group B(80%) with triage tool performed better in triaging the bomb blast victims than group A(50%) without the bombing specific triage tool performed.CONCLUSION: Development of bombing specific triage tool can reduce under triaging.展开更多
The sequential dispersing results of aerial cluster bomb are discussed. The ballistic model and the mod- el for impact point distribution of bullets are established. The main factors influencing impact point distribut...The sequential dispersing results of aerial cluster bomb are discussed. The ballistic model and the mod- el for impact point distribution of bullets are established. The main factors influencing impact point distribution are analyzed by numerical simulation. And the feasibility of improving distribution effect through sequential dis- persing is validated. Sequential dispersion and optimized airdrop parameters can help to achieve better battle effec- tiveness.展开更多
The buried village is Vinh Moc where more than 1200 Vietnamese, including soldiers, who lived underground during the Vietnam War (1965 to 1972) were hand dug into red basalt bedrock. The Vinh Moc Village was strategic...The buried village is Vinh Moc where more than 1200 Vietnamese, including soldiers, who lived underground during the Vietnam War (1965 to 1972) were hand dug into red basalt bedrock. The Vinh Moc Village was strategically located on the border of North Vietnam and South Vietnam approximately 14 km north of the DMZ and along the shoreline of the South China Sea. During the Vietnam War, the US Air Force heavily bombed Vinh Moc. The North Vietnamese Army (NVA) had an important military base on nearby Con Co Island. Brave civil volunteers from Vinh Moc would make the 28 km dangerous journey to the island, disguised as fishermen, to deliver supplies to the soldiers stationed there. The people who remained at Vinh Moc dug tunnels into red basalt hills in order to survive this onslaught. The American forces assessed the villagers of Vinh Moc were supplying food and armaments to the NVA garrison on the island of Con Co, which was in turn hindering the American bombers on their way to bomb Hanoi. The US military objective was to force the villagers of Vinh Moc to leave the area. The villagers initially dug the tunnels to a 10 m depth but the American forces designed bombs that burrowed down 10 m before exploding. The soil tunnels were then deepened to 30 m to provide safety for the soldiers and civilians working there during the intense US Air Force bombing. The primary objective of the research study was to determine how the soils and parent material of Vinh Moc Village, protected their villagers from the United States Air Force bombardment during the Vietnam War. In addition, the natural parent material at both the Vinh Moc and Cu Chi were assessed to determine why the tunnels were so resilient. The Cu Chi and Iron Triangle soil tunnels were dug by hand in the Old Alluvium soils and parent material where iron in solution precipitated and became the soil binding material. The Vinh Moc tunnels were hand dug in porous, red basalt (bedrock) hills where the consolidated rock structure itself provided the required binding material. Neither site needed support beams to hold up the ceilings.展开更多
An upsurge of terrorist activity has occurred in the past two decades. As part of this, explosive devices continue to be extensively deployed against civilians in wide-ranging environments. Bombings remain the leading...An upsurge of terrorist activity has occurred in the past two decades. As part of this, explosive devices continue to be extensively deployed against civilians in wide-ranging environments. Bombings remain the leading worldwide cause of civilian fatalities due to terrorism. This demands an understanding of modern terrorist bombing trends to inform mitigation strategy. The objective of this study was to identify the occurrence and severity of bombings against civilian targets in diverse attack settings, and to establish corresponding blast injury profiles. Data was obtained from analysis of the Global Terrorism Database(GTD) and a meta-analysis of blast injury data derived from the PubMed database. Closed environment explosions were associated with significantly greater(p<0.05) mortality than in open spaces. The injury profiles were found to be influenced by attack setting, with higher rates of primary injury on trains and buses, and secondary injury in open space.展开更多
Background:Since the 1970 s,terrorist bombings in subways have been frequently occurring worldwide.To cope with this threat and to provide medical response countermeasures,we analyzed the characteristics of subway bom...Background:Since the 1970 s,terrorist bombings in subways have been frequently occurring worldwide.To cope with this threat and to provide medical response countermeasures,we analyzed the characteristics of subway bombing terrorist attacks and used the Haddon matrix to explore medical response strategies.Methods:First,we analyzed 111 subway bombings from 1970 to 2017 recorded in the Global Terrorism Database to provide a reference for the strategy exploration.Then,we convened an expert panel to use the Haddon matrix to explore the medical response strategies to subway bombings.Results:In recent decades,at least one bombing attack occurs every 3 years.Summarized by the Haddon matrix,the influencing factors of medical responses to conventional subway bombings include the adequacy of first-aid kits and the medical evacuation equipment,the traffic conditions affecting the evacuation,the continuity and stability of communication,as well as the factors exclusively attributed to dirty bomb attacks in subways,such as ionizing radiation protection capabilities,the structure of the radiation sickness treatment network based on the subway lines,and the disposal of radioactive sewage.These factors form the basis of the strategy discussion.Conclusions:Since subway bombings are long-term threats,it is necessary to have proper medical response preparation.Based on the Haddon matrix,we explored the medical response strategies for terrorist subway bombings,especially dirty bomb attacks.Haddon matrix can help policymakers systematically find the most important factors,which makes the preparations of the response more efficient.展开更多
In order to numerically evaluate the acoustic characteristics of liquid rocket engine thrust chambers by means of a computational fluid dynamics method, a mathematical model of an artificial constant-volume bomb is pr...In order to numerically evaluate the acoustic characteristics of liquid rocket engine thrust chambers by means of a computational fluid dynamics method, a mathematical model of an artificial constant-volume bomb is proposed in this paper. A localized pressure pulse with a very high amplitude can be imposed on specified regions in a combustion chamber, the numerical procedure of which is described. Pressure oscillations actuated by the released constant-volume bomb can then be analyzed via Fast Fourier Transformation(FFT), and their modes can be identified according to the theoretical acoustic eigenfrequencies of the thrust chamber. The damping performances of the corresponding acoustic modes are evaluated by the half-power bandwidth method. The predicted acoustic characteristics and their damping for a special engine combustor agree well with the experimental data, validating the mathematical model and its numerical procedures. A small-thrust liquid rocket engine chamber is then analyzed by the present model. The First Longitudinal(1L) acoustic mode can be excited easily and is hard to be damped. The axial position of the central constantvolume bomb has little influence on the amplitude and damping capacity of the First Radial(1R) and 1L acoustic modes. Tangential acoustic modes can only be triggered by an off-centered constant-volume bomb, among which the First Tangential(1T) mode is the strongest and regarded as the most harmful one. The amplitude of the 1L acoustic mode is smaller, but its damping factor is larger, as a constant-volume bomb is imposed approaching the injector face. These results are contributed to evaluate the acoustic characteristics and their damping of the combustion chamber.展开更多
PIT tests are usually performed when a mass distribution of High Explosive(H.E) projectile fragments is required. This paper shows the underwater detonation effects of 60 mm, M90 H.E. mortar bomb filled with Comp. B o...PIT tests are usually performed when a mass distribution of High Explosive(H.E) projectile fragments is required. This paper shows the underwater detonation effects of 60 mm, M90 H.E. mortar bomb filled with Comp. B on cylindrical concrete structure(concrete pipe closed at one end-similar to a PIT test)which is 2 m high(inner height) with inner diameter of also 2 m. Thickness of both wall and bottom of a pipe is 0.35 m. Detailed characteristics of concrete which is used for manufacturing of a pipe are specified. Mortar bomb is submerged directly in to the water(no free airspace around the bomb) with the nose pointing to the bottom of a pipe. Number and mass of fragments after detonation are presented by table and photographs. Fragments of dummy fuze, through which blasting cap was protruded, are collected and reassembled to form a shape of a fuze after detonation where expanding of fuze material due to a detonation products is visualized. After underwater detonation, detonation of the same mortar bomb is performed in an empty pipe and the effects of this kind of detonation are observed. Distance at which fragments generated from submerged mortar bomb will not reach concrete pipes wall is also determined.展开更多
When considering the bomb explosion damage effect,the air shock wave and high-speed fragments of the bomb case are two major threats.In experiments,the air shock wave was studied by the bare explosives superseding the...When considering the bomb explosion damage effect,the air shock wave and high-speed fragments of the bomb case are two major threats.In experiments,the air shock wave was studied by the bare explosives superseding the real cased bomb;in contrast,the bomb case influence was ignored to reduce risk.The air explosion simulations of the MK84 warhead with and without the case were conducted.The numerical simulation results showed that the bomb case significantly influenced the shock wave generated by the bomb:the spatial distribution of shock wave in the near field changed,and the peak value of shock wave was reduced.Breakage of the case and kinetic energy of the fragmentation consumed 3 and 38% of the explosion energy,respectively.The increasing factors of the peak overpressure induced by the bare explosive on the ground and in the air were 1.43-3.04 and 1.37-1.57,respectively.Four typical stages of case breakage were defined.The mass distribution of the fragments follows the Mott distribution.The initial velocity distribution of the fragments agreed well with the Gurney equation.展开更多
Background: In radiological emergencies with radionuclide incorporation, decorporation treatment is particularly effective if started early. Treating all people potentially contaminated("urgent treatment") m...Background: In radiological emergencies with radionuclide incorporation, decorporation treatment is particularly effective if started early. Treating all people potentially contaminated("urgent treatment") may require large antidote stockpiles. An efficacious way to reduce antidote requirements is by using radioactivity screening equipment. We analyzed the suitability of such equipment for triage purposes and determined the most efficient mix of screening units and antidote daily doses.Methods: The committed effective doses corresponding to activities within the detection limits of monitoring portals and mobile whole-body counters were used to assess their usefulness as triage tools. To determine the optimal resource mix, we departed from a large-scale scenario(60,000 victims) and based on purchase prices of antidotes and screening equipment in Germany, we calculated efficiencies of different combinations of medical countermeasure resources by data envelopment analysis. Cost-effectiveness was expressed as the costs per life year saved and compared to risk reduction opportunities in other sectors of society as well as the values of a statistical life.Results: Monitoring portals are adequate instruments for a sensitive triage after cesium-137 exposure with a high screening throughput. For the detection of americium-241 whole-body counters with a lower daily screening capacity per unit are needed. Assuming that 1% of the potentially contaminated patients actually need decorporation treatment, an efficient resource mix includes 6 monitoring portals and 25 mobile whole-body counters. The optimum mix depends on price discounts and in particular the fraction of victims actually needing treatment. The costeffectiveness of preparedness for a "dirty bomb" attack is less than for common health care, but costs for a life year saved are less than for many risk-reduction interventions in the environmental sector.Conclusion: To achieve economic efficiency a high daily screening capacity is of major importance to substantially decrease the required amount of antidote doses. Among the determinants of the number of equipment units needed, the fraction of the potentially contaminated victims that actually needs treatment is the most difficult to assess. Judging cost-effectiveness of the preparedness for "dirty bomb" attacks is an issue of principle that must be dealt with by political leaders.展开更多
Oral drugs have been widely used in clinical therapy, but their developments were severely limited by the side effects of drug exposure as well as the multiple biological barriers. In this study, we constructed a “cl...Oral drugs have been widely used in clinical therapy, but their developments were severely limited by the side effects of drug exposure as well as the multiple biological barriers. In this study, we constructed a “cluster bomb” oral drug delivery system (DOX@PFeL@L100) with core-shell structure to overcome the complex absorption barriers. The inner core termed as “bomb” that contains a lot of ultra-small diameter Fe_(3)O_(4) nanoparticles (DOX@PFeL NPs) loaded with doxorubicin (DOX) and modified with l-valine, which can efficiently penetrate the epithelial cells via PePT1 receptor mediated endocytosis. The outer shell of this “cluster bomb” is a layer of pH-sensitive polymer (Eudragit®L100) that can be served as a pH-responsive switch and effectively control the “bomb” release in the intestinal microenvironment to improve the antitumor efficiency by the Fenton like reaction of DOX and Fe^(2+)/Fe^(3+). This study demonstrates that the “cluster comb” oral drug delivery system can sequentially overcome the multiple biological barriers, providing a safe and effective approach for tumor therapy.展开更多
Blast wall can prevent vehicles from approaching the protective building and can reduce the destructive power of shock wave to a certain extent.However,majority of studies on blast walls have some shortcomings.The exp...Blast wall can prevent vehicles from approaching the protective building and can reduce the destructive power of shock wave to a certain extent.However,majority of studies on blast walls have some shortcomings.The explosion test data are few.Most exsiting studies focus on the propagation of shock wave and the influence of blast wall on the propagation of shock wave.Discussion on the main parameters of blast wall design is meagre,such as the design of safety distance,the distance from the blast wall to the protective building,height and width of the blast wall.This paper uses the finite element programme LS-DYNA to design the blast wall.To analyze the convergence of the finite element model and to determine the mesh size of the model,this paper establishes several finite element models with different sizes of meshes to verify the model.Then,the overpressure distribution of the shock wave on the protective building is simulated to implement the blast wall design.The geometric parameters of the blast wall are preliminarily determined.And the influence of the safety distance on the overpressure of the building surface is mainly discussed,so as to determine the final design parameters.When the overpressure is less than 2 kPa,it is considered that there will be no damage to people caused by flying fragments.Eventually,the blast wall height is 3 m,the thickness is 1 m,and the safety distance is 35 m.The proposed method is used to demonstrate the design method,and the final design parameters of the blast wall can thus be used for reference.展开更多
In the case of a terrorist attack by a“dirty bomb”,blast injuries,external irradiation and the incorporation of radioactivity are to be expected.Departing from information about the radiological attack scenario with...In the case of a terrorist attack by a“dirty bomb”,blast injuries,external irradiation and the incorporation of radioactivity are to be expected.Departing from information about the radiological attack scenario with cesium-137 in the U.S.National Scenario Planning Guide,we estimated the radiological doses absorbed.Similar calculations were performed for a smaller plume size and a detonation in a subway.For conditions as described in the U.S.scenario,the committed effective dose amounted to a maximum of 848 mSv,even for very unfavorable conditions.Red bone marrow equivalent doses are insufcient to induce acute radiation sickness(ARS).In the case of a smaller plume size,the ARS threshold may be exceeded in some cases.In a subway bombing,doses are much higher and the occurrence of ARS should be expected.The health hazards from a dirty bomb attack will depend on the location and the explosive device.The derived Haddon matrix indicates that preparing for such an event includes education of all the medical staff about radiation effects,the time lines of radiation damages and the treatment priorities.Further determinants of the outcome include rapid evacuation even from difficult locations,the availability of a specific triage tool to rapidly identify victims at risk for ARS,the availability of an antidote stockpile and dedicated hospital beds to treat seriously irradiated victims.展开更多
The military situation of the thirteenth century required that the Song and the Mongols construct a great number of defensive works,relying on the mountains or facing the rivers,in the mountainous Sichuan Province and...The military situation of the thirteenth century required that the Song and the Mongols construct a great number of defensive works,relying on the mountains or facing the rivers,in the mountainous Sichuan Province and Chongqing.In recent years,a special kind of explosive firearms,huolei火雷(bombs),was unearthed in the large-scale excavations of the site of Diaoyu Fortress钓鱼城in Hechuan District合川and the Baidicheng白帝城in Fengjie County奉节,both of which were defensive works constructed in this mountainous area during the Southern Song dynasty.In addition,the ruins of kilns and the clay molds that were relevant to the casting of iron huolei have been discovered at the site of Baidicheng,indicating that these huolei might have been produced locally.The Southern Song iron huolei unearthed in Chongqing are the most direct evidence of the evolvement of gunpowder and firearms,and are of great significance to the history of science and technology,in particular the history of military technology.展开更多
The world’s earliest bomb with an iron casing,the iron huopao鐵火砲(cast-iron bomb,also referred to as zhentian lei震天雷,literally“thunder-crash bomb”),is one of the most important inventions of ancient China rela...The world’s earliest bomb with an iron casing,the iron huopao鐵火砲(cast-iron bomb,also referred to as zhentian lei震天雷,literally“thunder-crash bomb”),is one of the most important inventions of ancient China relating to gunpowder and firearms.Until recently,however,academics were not able to conduct substantial research on the topic,as no actual remains of a huopao had yet been found.Since 2013,in the excavation of two sites of Southern Song ancient cities(Diaoyu Fortress and Baidicheng)in Chongqing,archaeologists from the Chongqing Cultural Heritage Research Institute have discovered a number of iron huopao of the Southern Song dynasty.This finding not only provides first-hand material for research on the history of the invention of gunpowder and firearms,which has always been lacking,but also offers new physical evidence for an exploration of the history of war and the military history of the thirteenth century(in particular the Mongol-Song war),and is thus historically significant.展开更多
A wide spectrum of scenarios may lead to radiation incidents and the liberation of radioactive material. In the case of a terrorist attack by a "dirty bomb", there is a risk of mechanical and thermal trauma,...A wide spectrum of scenarios may lead to radiation incidents and the liberation of radioactive material. In the case of a terrorist attack by a "dirty bomb", there is a risk of mechanical and thermal trauma, external irradiation, superficial contamination and incorporation of radioactive material. The first treatment priority must be given to the care of trauma patients with life-threatening injuries, as the health effects of radiation occur with latency. Radionuclide incorporation will lead to a longer-lasting irradiation from inside the body, associated with a higher risk of stochastic radiation effects(e.g., occurrence of tumors) in the long run. It must be expected that victims with potentially incorporated radionuclides will far outnumber trauma patients. The elimination of radionuclides can be enhanced by the administration of decorporation agents such as(Ca) Diethylenetriaminepentaacetic acid(DTPA) or Prussian blue,reducing the radiological burden of the body. There is still no consensus whether decorporation treatment should be started immediately based only on a suspicion of radionuclide incorporation("urgent approach") or if the results of internal dosimetry confirming the necessity of a treatment should be awaited, accepting the delay caused by the measurements and computations("precautionary approach"). As the therapeutic effectiveness may be substantially decreased if treatment initiation is delayed only by several days, depending on the radionuclide, the physicochemical properties of the compounds involved and the route of absorption, we favor an "urgent approach" from a medical point of view. In doubt, it seems justified to treat victims by precaution, as the adverse effects of the medication seem minimal. However, in the case of a high number of victims, an "urgent treatment approach" may require a large number of daily doses of antidotes, and therefore, adequate investments in preparedness and antidote stockpiling are necessary.展开更多
文摘The legacy of United States cluster munition use in Laos and Cambodia during the Second Indochina War is residual bomblets that unexpectedly detonate years later, killing and injuring children, farmers, and other civilians. Cluster munitions release dozens of smaller bomblets that rain deadly ammunition on troops, armored tanks, and vegetation, effectively striking broad sections of war zone landscapes in one launch. While many bomblets detonate immediately, others fail to detonate and can lie dormant on the ground for years. The primary objectives of this study were to document the long-term consequences and impacts of the US Air Force bombing of Laos and Cambodia during the Second Indochina War (1959 to 1973). The historical lessons learned by United States should be shared with Russia and Ukraine governments and military. These countries need to discontinue the use of cluster bombs to prevent additional people living along the Russia-Ukraine border from having to live and die with the consequences of unexploded ordnance, including cluster bombs, for the next century.
基金supported by the National Natural Science Foundation of China(Grant No.42030410)the Laoshan Laboratory(Grant Nos.LSKJ202202404 and LSKJ202202403)+1 种基金the Startup Foundation for Introducing Tal-ent of NUIST,Jiangsu Innovation Research Group(Grant No.JSS-CTD202346)the Jiangsu Funding Program for Excellent Post-doctoral Talent(Grant No.2023ZB690).
文摘Bomb cyclones are rapidly deepening extratropical cyclones predominantly found in midlatitude regions.These extreme events are particularly frequent over the North Pacific(NP),posing significant societal and environmental risks.Currently,our understanding of the variability of bomb cyclones over the NP remains limited.This study analyzes the variations in multiple NP bomb cyclone characteristics from 1980 onward using four major reanalysis datasets.The results show a weakening trend of bomb cyclones since the beginning of the 21st century,which is characterized by significant reductions in maximum near-surface wind speeds,increases in minimum sea level pressure,and slower deepening rates.Further analysis reveals that the observed weakening trend of bomb cyclones is closely linked to a reduction in maximum 850 hPa Eady growth rate,driven primarily by reduced vertical wind shear within the 30°-45°N latitudinal band.Furthermore,our findings indicate that the Aleutian Low acts to modulate the meridional air temperature gradient over the midlatitude NP,which is corroborated by climate model outputs.This modulation provides a pathway for the Aleutian Low to affect low-level baroclinicity and thus bomb cyclone characteristics.These results have important implications for future projections of bomb cyclone activity over the NP,aiding in risk assessment and mitigating the impacts of these extreme events.
基金supported by the National Natural Science Foundation of China(No.81972892)。
文摘Lung cancer is one of the most common malignant tumors with the fastest increase in the incidence rate and mortality.Even after maximum tumor resection assistance with a radiotherapy and chemotherapy combination,the recurrence of non-small cell lung cancer is still inevitable.In addition,low targeting efficiency and poor permeability of drug delivery systems strongly affect the therapeutic efficiency of anti-cancer drugs on non-small cell lung cancer.Here we designed a gemcitabine(GEM)loaded arginineglycine-aspartic acid-cysteine(RGDc)-modified gold mineralization“hybrid nanozyme bomb”(RGTG)to overcome those obstacles.RGDc modification improved the active targeting of liposomes to the tumor tissues with the second near-infrared(NIR-Ⅱ)-triggered gold-shell disruption and GEM release.The collapsed gold-shell particles with a smaller size could penetrate the tumor solid barrier and act as photothermal therapy(PTT)agents to improve PTT therapy and starvation therapy via generating gluconic acid and reactive oxygen species(ROS).Moreover,the resting reversal effect of gold particles on tumor fibroblasts can achieve accelerating tumor penetration of gold particles and GEM.Compared to monotherapy,RGTG showed significant improvement in tumor inhibition,with a tumor volume reduction of 83%compared to the control group,which provides a promising tumor treatment platform for non-small cell lung cancer(NSCLC).
基金This work was supported by the major research projects within the military-international class(JY2021B077).
文摘The laser-guided bomb(LGB)is an air-to-ground pre-cision-guided weapon that offers high hit rates,great power,and ease of use.LGBs are guided by semi-active laser ground-seek-ing technology,which means that atmospheric conditions can affect their accuracy.The spatial release region(SRR)of LGBs is difficult to calculate precisely,especially when there is a poor field of view.This can result in a lower real hit probability.To increase the hit probability of LGBs in tough atmospheric situa-tions,a novel method for calculating the SRR has been pro-posed.This method is based on the transmittance model of the 1.06μm laser in atmospheric species and the laser diffuse reflection model of the target surface to determine the capture target time of the laser seeker.Then,it calculates the boundary ballistic space starting position by ballistic model and gets the spatial scope of the spatial release region.This method can determine the release region of LGBs based on flight test data such as instantaneous velocity,altitude,off-axis angle,and atmospheric visibility.By more effectively employing aircraft release conditions,atmospheric visibility and other factors,the SRR calculation method can improve LGB hit probabi-lity by 9.2%.
文摘BACKGROUND: Bombing is a unique incident which produces unique patterns, multiple and occult injuries. Death often is a result of combined blast, ballistic and thermal effect injuries. Various natures of injury, self referrals and arrival by private transportation may lead to "wrong triage" in the emergency department. In India there has been an increase in incidence of bombing in the last 15 years. There is no documented triage tool from the National Disaster Management Authority of India for Bombings. We have tried to develop an ideal bombing specific triage tool which will guide the right patients to the right place at the right time and save more lives.METHODS: There are three methods of studying the triage tool: 1) real disaster; 2) mock drill; 3) table top exercise. In this study, a table top exercise method was selected. There are two groups, each consisting of an emergency physician, a nurse and a paramedic.RESULTS: By using the proportion test, we found that correct triaging was significantly different(P=0.005) in proportion between the two groups: group B(80%) with triage tool performed better in triaging the bomb blast victims than group A(50%) without the bombing specific triage tool performed.CONCLUSION: Development of bombing specific triage tool can reduce under triaging.
基金Supported by the Independent Scientific Research of Nanjing University of Science and Technology(2011YBXM110)~~
文摘The sequential dispersing results of aerial cluster bomb are discussed. The ballistic model and the mod- el for impact point distribution of bullets are established. The main factors influencing impact point distribution are analyzed by numerical simulation. And the feasibility of improving distribution effect through sequential dis- persing is validated. Sequential dispersion and optimized airdrop parameters can help to achieve better battle effec- tiveness.
文摘The buried village is Vinh Moc where more than 1200 Vietnamese, including soldiers, who lived underground during the Vietnam War (1965 to 1972) were hand dug into red basalt bedrock. The Vinh Moc Village was strategically located on the border of North Vietnam and South Vietnam approximately 14 km north of the DMZ and along the shoreline of the South China Sea. During the Vietnam War, the US Air Force heavily bombed Vinh Moc. The North Vietnamese Army (NVA) had an important military base on nearby Con Co Island. Brave civil volunteers from Vinh Moc would make the 28 km dangerous journey to the island, disguised as fishermen, to deliver supplies to the soldiers stationed there. The people who remained at Vinh Moc dug tunnels into red basalt hills in order to survive this onslaught. The American forces assessed the villagers of Vinh Moc were supplying food and armaments to the NVA garrison on the island of Con Co, which was in turn hindering the American bombers on their way to bomb Hanoi. The US military objective was to force the villagers of Vinh Moc to leave the area. The villagers initially dug the tunnels to a 10 m depth but the American forces designed bombs that burrowed down 10 m before exploding. The soil tunnels were then deepened to 30 m to provide safety for the soldiers and civilians working there during the intense US Air Force bombing. The primary objective of the research study was to determine how the soils and parent material of Vinh Moc Village, protected their villagers from the United States Air Force bombardment during the Vietnam War. In addition, the natural parent material at both the Vinh Moc and Cu Chi were assessed to determine why the tunnels were so resilient. The Cu Chi and Iron Triangle soil tunnels were dug by hand in the Old Alluvium soils and parent material where iron in solution precipitated and became the soil binding material. The Vinh Moc tunnels were hand dug in porous, red basalt (bedrock) hills where the consolidated rock structure itself provided the required binding material. Neither site needed support beams to hold up the ceilings.
基金support of the Institute for Security Science and TechnologyThe Royal British Legion Centre for Blast Injury Studies at Imperial College LondonThe Institute of Shock Physics also acknowledges the support of Imperial College London
文摘An upsurge of terrorist activity has occurred in the past two decades. As part of this, explosive devices continue to be extensively deployed against civilians in wide-ranging environments. Bombings remain the leading worldwide cause of civilian fatalities due to terrorism. This demands an understanding of modern terrorist bombing trends to inform mitigation strategy. The objective of this study was to identify the occurrence and severity of bombings against civilian targets in diverse attack settings, and to establish corresponding blast injury profiles. Data was obtained from analysis of the Global Terrorism Database(GTD) and a meta-analysis of blast injury data derived from the PubMed database. Closed environment explosions were associated with significantly greater(p<0.05) mortality than in open spaces. The injury profiles were found to be influenced by attack setting, with higher rates of primary injury on trains and buses, and secondary injury in open space.
文摘Background:Since the 1970 s,terrorist bombings in subways have been frequently occurring worldwide.To cope with this threat and to provide medical response countermeasures,we analyzed the characteristics of subway bombing terrorist attacks and used the Haddon matrix to explore medical response strategies.Methods:First,we analyzed 111 subway bombings from 1970 to 2017 recorded in the Global Terrorism Database to provide a reference for the strategy exploration.Then,we convened an expert panel to use the Haddon matrix to explore the medical response strategies to subway bombings.Results:In recent decades,at least one bombing attack occurs every 3 years.Summarized by the Haddon matrix,the influencing factors of medical responses to conventional subway bombings include the adequacy of first-aid kits and the medical evacuation equipment,the traffic conditions affecting the evacuation,the continuity and stability of communication,as well as the factors exclusively attributed to dirty bomb attacks in subways,such as ionizing radiation protection capabilities,the structure of the radiation sickness treatment network based on the subway lines,and the disposal of radioactive sewage.These factors form the basis of the strategy discussion.Conclusions:Since subway bombings are long-term threats,it is necessary to have proper medical response preparation.Based on the Haddon matrix,we explored the medical response strategies for terrorist subway bombings,especially dirty bomb attacks.Haddon matrix can help policymakers systematically find the most important factors,which makes the preparations of the response more efficient.
基金Financial support from the National Natural Science Foundation of China (Nos.51676111 and 11628206)
文摘In order to numerically evaluate the acoustic characteristics of liquid rocket engine thrust chambers by means of a computational fluid dynamics method, a mathematical model of an artificial constant-volume bomb is proposed in this paper. A localized pressure pulse with a very high amplitude can be imposed on specified regions in a combustion chamber, the numerical procedure of which is described. Pressure oscillations actuated by the released constant-volume bomb can then be analyzed via Fast Fourier Transformation(FFT), and their modes can be identified according to the theoretical acoustic eigenfrequencies of the thrust chamber. The damping performances of the corresponding acoustic modes are evaluated by the half-power bandwidth method. The predicted acoustic characteristics and their damping for a special engine combustor agree well with the experimental data, validating the mathematical model and its numerical procedures. A small-thrust liquid rocket engine chamber is then analyzed by the present model. The First Longitudinal(1L) acoustic mode can be excited easily and is hard to be damped. The axial position of the central constantvolume bomb has little influence on the amplitude and damping capacity of the First Radial(1R) and 1L acoustic modes. Tangential acoustic modes can only be triggered by an off-centered constant-volume bomb, among which the First Tangential(1T) mode is the strongest and regarded as the most harmful one. The amplitude of the 1L acoustic mode is smaller, but its damping factor is larger, as a constant-volume bomb is imposed approaching the injector face. These results are contributed to evaluate the acoustic characteristics and their damping of the combustion chamber.
文摘PIT tests are usually performed when a mass distribution of High Explosive(H.E) projectile fragments is required. This paper shows the underwater detonation effects of 60 mm, M90 H.E. mortar bomb filled with Comp. B on cylindrical concrete structure(concrete pipe closed at one end-similar to a PIT test)which is 2 m high(inner height) with inner diameter of also 2 m. Thickness of both wall and bottom of a pipe is 0.35 m. Detailed characteristics of concrete which is used for manufacturing of a pipe are specified. Mortar bomb is submerged directly in to the water(no free airspace around the bomb) with the nose pointing to the bottom of a pipe. Number and mass of fragments after detonation are presented by table and photographs. Fragments of dummy fuze, through which blasting cap was protruded, are collected and reassembled to form a shape of a fuze after detonation where expanding of fuze material due to a detonation products is visualized. After underwater detonation, detonation of the same mortar bomb is performed in an empty pipe and the effects of this kind of detonation are observed. Distance at which fragments generated from submerged mortar bomb will not reach concrete pipes wall is also determined.
文摘When considering the bomb explosion damage effect,the air shock wave and high-speed fragments of the bomb case are two major threats.In experiments,the air shock wave was studied by the bare explosives superseding the real cased bomb;in contrast,the bomb case influence was ignored to reduce risk.The air explosion simulations of the MK84 warhead with and without the case were conducted.The numerical simulation results showed that the bomb case significantly influenced the shock wave generated by the bomb:the spatial distribution of shock wave in the near field changed,and the peak value of shock wave was reduced.Breakage of the case and kinetic energy of the fragmentation consumed 3 and 38% of the explosion energy,respectively.The increasing factors of the peak overpressure induced by the bare explosive on the ground and in the air were 1.43-3.04 and 1.37-1.57,respectively.Four typical stages of case breakage were defined.The mass distribution of the fragments follows the Mott distribution.The initial velocity distribution of the fragments agreed well with the Gurney equation.
文摘Background: In radiological emergencies with radionuclide incorporation, decorporation treatment is particularly effective if started early. Treating all people potentially contaminated("urgent treatment") may require large antidote stockpiles. An efficacious way to reduce antidote requirements is by using radioactivity screening equipment. We analyzed the suitability of such equipment for triage purposes and determined the most efficient mix of screening units and antidote daily doses.Methods: The committed effective doses corresponding to activities within the detection limits of monitoring portals and mobile whole-body counters were used to assess their usefulness as triage tools. To determine the optimal resource mix, we departed from a large-scale scenario(60,000 victims) and based on purchase prices of antidotes and screening equipment in Germany, we calculated efficiencies of different combinations of medical countermeasure resources by data envelopment analysis. Cost-effectiveness was expressed as the costs per life year saved and compared to risk reduction opportunities in other sectors of society as well as the values of a statistical life.Results: Monitoring portals are adequate instruments for a sensitive triage after cesium-137 exposure with a high screening throughput. For the detection of americium-241 whole-body counters with a lower daily screening capacity per unit are needed. Assuming that 1% of the potentially contaminated patients actually need decorporation treatment, an efficient resource mix includes 6 monitoring portals and 25 mobile whole-body counters. The optimum mix depends on price discounts and in particular the fraction of victims actually needing treatment. The costeffectiveness of preparedness for a "dirty bomb" attack is less than for common health care, but costs for a life year saved are less than for many risk-reduction interventions in the environmental sector.Conclusion: To achieve economic efficiency a high daily screening capacity is of major importance to substantially decrease the required amount of antidote doses. Among the determinants of the number of equipment units needed, the fraction of the potentially contaminated victims that actually needs treatment is the most difficult to assess. Judging cost-effectiveness of the preparedness for "dirty bomb" attacks is an issue of principle that must be dealt with by political leaders.
基金supported by the National Natural Science Foundation of China (Nos. 81773276, 81972907, 81874304, and U1804183)Key Scientific Research Project (Education Department of Henan Province)(No. 20HASTIT049)Modern Analysis and Computer Center of Zhengzhou University。
文摘Oral drugs have been widely used in clinical therapy, but their developments were severely limited by the side effects of drug exposure as well as the multiple biological barriers. In this study, we constructed a “cluster bomb” oral drug delivery system (DOX@PFeL@L100) with core-shell structure to overcome the complex absorption barriers. The inner core termed as “bomb” that contains a lot of ultra-small diameter Fe_(3)O_(4) nanoparticles (DOX@PFeL NPs) loaded with doxorubicin (DOX) and modified with l-valine, which can efficiently penetrate the epithelial cells via PePT1 receptor mediated endocytosis. The outer shell of this “cluster bomb” is a layer of pH-sensitive polymer (Eudragit®L100) that can be served as a pH-responsive switch and effectively control the “bomb” release in the intestinal microenvironment to improve the antitumor efficiency by the Fenton like reaction of DOX and Fe^(2+)/Fe^(3+). This study demonstrates that the “cluster comb” oral drug delivery system can sequentially overcome the multiple biological barriers, providing a safe and effective approach for tumor therapy.
基金This work was supported by the National Natural Science Foundation of China(No.51878507).
文摘Blast wall can prevent vehicles from approaching the protective building and can reduce the destructive power of shock wave to a certain extent.However,majority of studies on blast walls have some shortcomings.The explosion test data are few.Most exsiting studies focus on the propagation of shock wave and the influence of blast wall on the propagation of shock wave.Discussion on the main parameters of blast wall design is meagre,such as the design of safety distance,the distance from the blast wall to the protective building,height and width of the blast wall.This paper uses the finite element programme LS-DYNA to design the blast wall.To analyze the convergence of the finite element model and to determine the mesh size of the model,this paper establishes several finite element models with different sizes of meshes to verify the model.Then,the overpressure distribution of the shock wave on the protective building is simulated to implement the blast wall design.The geometric parameters of the blast wall are preliminarily determined.And the influence of the safety distance on the overpressure of the building surface is mainly discussed,so as to determine the final design parameters.When the overpressure is less than 2 kPa,it is considered that there will be no damage to people caused by flying fragments.Eventually,the blast wall height is 3 m,the thickness is 1 m,and the safety distance is 35 m.The proposed method is used to demonstrate the design method,and the final design parameters of the blast wall can thus be used for reference.
基金Bundeswehr Institute of Radiobiology,Neuherberg Str.1180937 Munich,Germany。
文摘In the case of a terrorist attack by a“dirty bomb”,blast injuries,external irradiation and the incorporation of radioactivity are to be expected.Departing from information about the radiological attack scenario with cesium-137 in the U.S.National Scenario Planning Guide,we estimated the radiological doses absorbed.Similar calculations were performed for a smaller plume size and a detonation in a subway.For conditions as described in the U.S.scenario,the committed effective dose amounted to a maximum of 848 mSv,even for very unfavorable conditions.Red bone marrow equivalent doses are insufcient to induce acute radiation sickness(ARS).In the case of a smaller plume size,the ARS threshold may be exceeded in some cases.In a subway bombing,doses are much higher and the occurrence of ARS should be expected.The health hazards from a dirty bomb attack will depend on the location and the explosive device.The derived Haddon matrix indicates that preparing for such an event includes education of all the medical staff about radiation effects,the time lines of radiation damages and the treatment priorities.Further determinants of the outcome include rapid evacuation even from difficult locations,the availability of a specific triage tool to rapidly identify victims at risk for ARS,the availability of an antidote stockpile and dedicated hospital beds to treat seriously irradiated victims.
文摘The military situation of the thirteenth century required that the Song and the Mongols construct a great number of defensive works,relying on the mountains or facing the rivers,in the mountainous Sichuan Province and Chongqing.In recent years,a special kind of explosive firearms,huolei火雷(bombs),was unearthed in the large-scale excavations of the site of Diaoyu Fortress钓鱼城in Hechuan District合川and the Baidicheng白帝城in Fengjie County奉节,both of which were defensive works constructed in this mountainous area during the Southern Song dynasty.In addition,the ruins of kilns and the clay molds that were relevant to the casting of iron huolei have been discovered at the site of Baidicheng,indicating that these huolei might have been produced locally.The Southern Song iron huolei unearthed in Chongqing are the most direct evidence of the evolvement of gunpowder and firearms,and are of great significance to the history of science and technology,in particular the history of military technology.
文摘The world’s earliest bomb with an iron casing,the iron huopao鐵火砲(cast-iron bomb,also referred to as zhentian lei震天雷,literally“thunder-crash bomb”),is one of the most important inventions of ancient China relating to gunpowder and firearms.Until recently,however,academics were not able to conduct substantial research on the topic,as no actual remains of a huopao had yet been found.Since 2013,in the excavation of two sites of Southern Song ancient cities(Diaoyu Fortress and Baidicheng)in Chongqing,archaeologists from the Chongqing Cultural Heritage Research Institute have discovered a number of iron huopao of the Southern Song dynasty.This finding not only provides first-hand material for research on the history of the invention of gunpowder and firearms,which has always been lacking,but also offers new physical evidence for an exploration of the history of war and the military history of the thirteenth century(in particular the Mongol-Song war),and is thus historically significant.
文摘A wide spectrum of scenarios may lead to radiation incidents and the liberation of radioactive material. In the case of a terrorist attack by a "dirty bomb", there is a risk of mechanical and thermal trauma, external irradiation, superficial contamination and incorporation of radioactive material. The first treatment priority must be given to the care of trauma patients with life-threatening injuries, as the health effects of radiation occur with latency. Radionuclide incorporation will lead to a longer-lasting irradiation from inside the body, associated with a higher risk of stochastic radiation effects(e.g., occurrence of tumors) in the long run. It must be expected that victims with potentially incorporated radionuclides will far outnumber trauma patients. The elimination of radionuclides can be enhanced by the administration of decorporation agents such as(Ca) Diethylenetriaminepentaacetic acid(DTPA) or Prussian blue,reducing the radiological burden of the body. There is still no consensus whether decorporation treatment should be started immediately based only on a suspicion of radionuclide incorporation("urgent approach") or if the results of internal dosimetry confirming the necessity of a treatment should be awaited, accepting the delay caused by the measurements and computations("precautionary approach"). As the therapeutic effectiveness may be substantially decreased if treatment initiation is delayed only by several days, depending on the radionuclide, the physicochemical properties of the compounds involved and the route of absorption, we favor an "urgent approach" from a medical point of view. In doubt, it seems justified to treat victims by precaution, as the adverse effects of the medication seem minimal. However, in the case of a high number of victims, an "urgent treatment approach" may require a large number of daily doses of antidotes, and therefore, adequate investments in preparedness and antidote stockpiling are necessary.