Scientists have devised a way to determine roughly where a person has lived using a strand (缕) of hair, a technique that could help track the movements of criminal suspects or unidentified murder victims.
The method relies on measuring how chemical variations in drinking water show up in people’s hair.
"You’re what you eat and drink, and that’s recorded in your hair," said Tilure Cerling, a geologist at the University of Utah.
While U. S. diet is relatively identical, water supplies vary. The differences result from weather patterns. The chemical composition of rainfall changes slightly as rain clouds move.
Most hydrogen and oxygen atoms in water are stable, but traces of both elements are also present as heavier isotopes (同位素). The heaviest rain falls first. As a result, storms that form over the Pacific deliver heavier water to California than to Utah.
Similar patterns exist throughout the U. S. By measuring th
A. Food and drink affect one’s personality development
B. Food and drink preferences vary with individuals
C. Food and drink leave traces in one’s body tissues
D. Food and drink are indispensable to one’s existence
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Irish Dolphins May Have a Unique
Dialect Irish scientists monitoring dolphins living in a river estuary in the southwest of the country believe they may have developed a unique dialect to communicate with each other. The Channel Dolphin and Wildlife Foundation (SDWF) has been studying a group of up to 120 bottle-nose dolphins in the River Shannon using vocalisations collected on a computer in a cow shed near the River Shannon. As part of a research project, student Ronan Hickey digitised and analysed a total of 1,882 whistles from the Irish dolphins and those from the Welsh dolphins on a computer and separated them into six fundamental whistle types and 32 different categories. Of the categories, he foun [单选题]以下哪个是目视模式（ ）
A.A、IS B.B、OS C.C、FS D.D、CS [多选题]防高温手套具有( )、防刺穿等性能。
A.防火 B.隔热 C.耐高温 D.防切割 [判断题]提高供电可靠性，是对电力部门的要求，与用户无关。
A.正确 B.错误 [单选题]省公司对市公司( )开展一次媒体投放、线下活动/物料印刷制作结算执行情况抽查。
A.月度 B.季度 C.半年 D.一年 [判断题]自贸区里的商品交易基本上是零关税。
[判断题]料面温度和炉压的关联关系：大负压必定导致料面温度升高
A.正确 B.错误 [单选题]接触网步行巡视不少于两人，其中一人的安全等级不低于( )
A. 二级 B. 三级 C. 四级 D. 五级 [单项选择]胸骨角平面，相当于（）
A. 第2、3胸椎 B. 第4、5胸椎 C. 第6胸椎 D. 第7、8胸椎 E. 第11胸椎 [判断题]事故紧急抢修工作，指用电设备发生故障被迫紧急停止运行，需短时间内恢复的抢修和排除故障的工作。
A.正确 B.错误 [判断题]严格意义上来讲，这种微混合动力系统的汽车属于真正的混合动力汽车
A.正确 B.错误 [多选题]开挖深度在3～5m之间的基坑挖土，应当遵循（）的规定。
A.挖土区域设警戒线，基槽两边顶部1.5m范围内，不得临时增加荷载 B.一般土质条件下弃土堆底至基坑顶边距离≥1m，弃土堆高≤1.5m。软土场地的基坑边则不应在基坑边堆土 C.垂直坑壁边坡条件下弃土堆底至基坑顶边距离≥3m D.机动车停稳后方可进行装土作业，挖斗严禁从驾驶室上方越过。挖掘机暂停工作时，挖斗放到地面上，不得悬空 E.施工作业点设可靠围栏及悬挂警告标示，夜间施工设红灯警示，并设监护人 [单项选择]患者男性，50岁，左下肢原发性性静脉曲张10年，半年前左内踝上方出现溃疡，大小约4cm×3cm，经久不愈。检查下肢深静脉有无异常，首选的方法是（）
A. 测下肢浅静脉区 B. 测下肢活动静脉压 C. 多普勒超声检查 D. 下肢静脉造影 E. 放射性核素检查 [单项选择]淋巴细胞的表面抗原的检测可用于T淋巴细胞的亚群分类、功能分析等。CD抗原是淋巴细胞表面的分化抗原。表达于成熟B细胞表面的CD分子是（）
A. CD10 B. CD21 C. CD28 D. CDl6 E. CD69 [多项选择]红细胞C6PD缺乏使红细胞膜受损包括（）
A. 通透性增加 B. 抗体性改变 C. 通透性不增加 D. 变形降低 E. 抗原性改变 [不定项选择题]共用题干
Scientists Develop Ways of Detecting Heart Attack
German researchers have___1___a new generation of defibrillators and earlywarning software aimed at offering heart patients greater protection___2___sudden death from cardiac arrest. In Germany alone around 100,000 people die annually as a result of cardiac arrest and many of these cases___3___by disruption to the heart's rhythm. Those most at risk are pa- tients who have___4___suffered a heart attack,and for years the use of defibrillators has proved useful in diagnosing___ 5___ disruptions to heart rhythms and correcting them automat-ically by intervening within seconds. These devices___6___ a range of functions,such as that of pacemaker. Heart specialists at Freiburg's University Clinic have now achieved a breakthrough with an implanted defibrillator ___7___of generating a six-channel electrocardiogram(EC G)within the body. This integrated system allows early diagnosis of___8___blood-flow problems and a pending heart attack. It will be implanted in patients for the first time this year. Meanwhile, researchers at the Fraunhofer Institute for Applied Mathematics in Kaiserslautern have developed new computer software that renders the evaluation of ECG data___9___. The overwhelming___10___of patients at risk will not have an implanted defibrillator and must for this reason undergo regular ECGs.“Many of the current programs only ___11___ into account a linear correlation of the data. We are,however,making use___12___ a non-linear process that reveals the chaotic patterns of heart beats as an open and complex system,” Hagen Knaf says,“___ 13___ changes in the heart beats over time can be monitored and indi- vidual variations in patients taken into account.”An old study of ECG data,based___14___ 600 patients who had suffered a subsequent heart attack,enabled the researchers to compare risks and to show___15___the new software evaluates the data considerably better. 7._________ A.capable B.able C.skillful D.skilled [单选题].与顾客交流时，应尽量（）。
A.直视对方 B.看向一旁 C.随意张望 D.看向地面 [判断题]接班后的第一批调车作业计划由当班车站调度员下达。
A.正确 B.错误 [单选题]69-4B型轻潜水装具是一种自携式潜水装置，配备 ( ) 和咬嘴型供需式供气阀，使用方便，安全可靠。
A.全面罩 B.半面罩 C.无面罩 D.都不是 [单选题]带电作业使用屏蔽服前，应用量程为0.1Ω～50Ω的电阻表对其检测，衣裤任意两个最远端点之间的电阻值均不应大于（）。
A.10Ω B.20Ω C.15Ω D.500Ω [不定项选择题]下列属于消防装备设施的是（ ）。
A.消防头盔 B.消防战斗服 C.空气呼吸器 D.消防手套 [单项选择]______是指每个像素颜色或灰度被量化后所占用的存储器位数。
A. 图像分辨率 B. 图像深度 C. 屏幕分辨率 D. 像素分辨率 [单选题]地方各级人民政府应当落实消防工作责任制，对（ ）履行消防安全职责的情况进行监督检查。
A. 各级人民政府部门 B. 消防救援机构 C. 应急管理部门 D. 本级人民政府有关部门 [单选题]在有触电危险的现场，要利用（ ）实施检测，并划定警戒区域。
A.有毒气体探测仪 B.漏电探测仪 C.可燃气体探测仪 D.测温仪 我来回答: 提交
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