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Are 3D mammograms better than standard imaging? A diverse study aims to find out_我的网站

武媚娘传奇

一 |     Are 3D mammograms better than standard 2D imaging for catching advanced cancers?A clinical trial is recruiting thousands of volunteers — including a large number of Black women who face disparities in breast cancer death rates — to try to find out.People like Carole Stovall, a psychologist in Washington, D.C., have signed up for the study to help answer the question.“We all need a mammogram anyway, so why not do it with a study that allows the scientists to understand more and move closer to finding better treatments and ways of maybe even preventing it?” Stovall said.The underrepresentation of women and minorities in research is a long-simmering issue affecting health problems including Alzheimer’s disease, stroke and COVID-19. Trials without diversity lead to gaps in understanding of how new treatments work for all people. “Until we get more Black women into clinical trials, we can’t change the science. And we need better science for Black bodies,” said Ricki Fairley, a breast cancer survivor and advocate who is working on the issue.Black women are 40% more likely to die from breast cancer than white women and tend to be diagnosed younger. But it’s not clear whether 3D mammography is better for them, said Dr. Worta McCaskill-Stevens of the National Cancer Institute.“Are there populations for whom this might be important to have early diagnosis?" asked McCaskill-Stevens. "Or is it harmful,” causing too many false alarms or unneeded follow-up tests and treatments?McCaskill-Stevens, who is Black, leads NCI’s efforts to boost access to cancer research in minority and rural communities. She has joined the study herself.The newer 3D technique has been around for a decade, but there’s never been conclusive evidence that it's better than 2D at detecting advanced cancers. The screening technique combines multiple pictures of the breast taken from different angles to create a 3D-like image. Both 3D and 2D mammograms compress the breast and use low doses of radiation.Prior studies suggest that 3D finds more cancers than 2D, but catching more cancers doesn’t necessarily mean more lives saved. Some cancers missed by standard screening may not progress or need treatment. Previous studies did not randomly assign patients to a screening method, the gold standard for research.The notion “that if it’s new, it’s shiny, then it’s better,” isn’t necessarily true, McCaskill-Stevens said. “Until we have the evidence to support that, then we need well-designed randomized trials.”The trial has enrolled nearly 93,000 women so far with a goal of 128,000. The NCI-funded study is now running in Canada, South Korea, Peru, Argentina, Italy and 32 U.S. states. A site in Thailand will soon begin enrolling patients.“We added more international sites to enhance the trial’s diversity, particularly for Hispanic and Asian women,” said Dr. Etta Pisano, who leads the study. Overall, 42% of participants are Hispanic. As recruiting continues, enrolling Black women and other women of color will “absolutely” continue as a priority, Pisano said.Participants are randomly assigned to either 2D or 3D mammograms and are followed for several years. The number of advanced cancers detected by the two methods will be compared.At the U.S. study sites, 21% of study participants are Black women — that's higher than a typical cancer treatment study, in which 9% of participants are Black, McCaskill-Stevens said.The University of North Carolina has signed up more Black women than any other study site. Nearly a quarter of the nearly 3,000 women enrolled at UNC’s two locations are Black.“Women in North Carolina want to take part in something that’s bigger than them,” said Dr. Cherie Kuzmiak, who leads the UNC arm of the study. “They want this active role in helping determine the future of health care for women.”In Washington, D.C., word of mouth has led to successful recruiting. A chance encounter at her hair salon persuaded Stovall to join the research. While waiting for a hair appointment, she met Georgetown University cancer researcher Lucile Adams-Campbell. The two, both Black, started chatting.“She explained how important it was to get women of color into the program,” said Stovall, who jumped at the chance to catch up on her mammograms after the COVID-19 pandemic delayed screening for her and thousands of others.For Stovall, there was a personal reason to join the research. Her sister recently completed treatment for triple negative breast cancer, an aggressive type that affects Black women at higher rates than white women. Women ages 45 to 74 without a personal history of breast cancer are eligible for the study, which launched in 2017. Many women also are providing blood and cheek swab samples for a database that will be mined for insights.“It’s a dream that people had since the beginning of screening that we wouldn’t fit everybody into the same box,” Pisano said. The study's findings could “reduce disparities if we’re successful, assuming people have access to care.”Stovall, 72, had a brief scare when her mammogram, the traditional 2D type, showed something suspicious. A biopsy ruled out cancer.“I was extremely relieved,” Stovall said. “Everybody I know has heard from me about the need for them to go get a mammogram.”___The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.。    

美国政府启动所谓“中美贸易战”六年后,又有了进一步升级的硝烟味。
5月14日,拜登政府公布了拖延已久的301关税复审报告,并宣布了进一步加征关税的方案。美国贸易谈判代表办公室近期还会公布细化的征税计划,在经过一定程序后付诸实施。目前,各机构正陆续发布分析报告。

二 | 这里我也想谈谈自己的看法。

很多人认为,拜登政府此次加征关税主要是基于竞选考量,包括美方的一些智库人士和媒体也这么说。

三 |

竞选考量有没有?当然有,而且是很重要的因素。特朗普曾经声称要对美国进口的中国投资者在墨西哥生产的电动车加征100%关税,结果拜登先针对从中国进口的电动车加征100%关税。

四 | 拜登的加税计划透露后,特朗普的回应是要对中国企业在墨西哥生产的汽车征收200%的关税。

五 | 比狠,谁也不较谁差。

2023年,中国出口到美国的纯电动汽车大约1.24万辆,金额合人民币约为23.55亿人民币。这个规模说大不大,说小不小。加征这个100%的关税后,估计这一万多辆的贸易额应该也就没有了。
光伏产品的反倾销反补贴关税加在一起,对于不同企业而言,低的在33%左右,高的超过250%;另外,还有14.25%(2025年降到14%)的201保障措施关税。在此基础上叠加的301关税从25%涨到50%,意味着目前很少的出口量,2023年334.7万美元的光伏电池片和1314.7万美元的光伏组件,在今后恐怕也会基本消失。
如果单纯看上述情况,相对整个产业规模来看,影响的金额不大,拜登这次加征关税确实边际影响有限,反而是在选民中塑造强硬形象的作用更大一些。但是,对于中国电动汽车和光伏产品来说,这次美国政府加税基本上就把对美直接出口的路堵死了。

六 |

那么,出海投资和中间产品出口的路子呢?特朗普不是扬言对从墨西哥进口的中国投资者生产的汽车也要加关税吗?这几年墨西哥市场很火,据说不少人去墨西哥投资,但对于墨西哥的经济前景,我还是存疑。
从2000年到2022年,对比各经济体在全球经济总量中的占比,下降幅度最大的发展中国家是墨西哥,从全球占比的2.20%下降到1.45%。明明相邻着这样一个世界第一大市场,为什么墨西哥会退步?因为它的经济政策难以自主,即使是出现对自己有利的机会,也难以充分利用。

七 |

特朗普打算围堵中国汽车的海外投资,拜登则已经开始对中国光伏的海外投资进行打压。4月24日,美国开始了对越南、柬埔寨、马来西亚和泰国的光伏开展双反调查程序,预计今年内初裁,明年年中终裁。目前提起调查的申请中列举的四国倾销幅度从70.35%到271.45%不等,大有一次堵死四国对美光伏出口之势。
虽然直接涉及的电动车和光伏产品贸易金额有限,这次美国加税涉及的总金额是180亿美元,大体占中国输美产品4.2%的规模,但这180亿美元是在301关税打压将近六年之后的数字,是一笔不小的金额,其中锂电池在这180亿美元中占了三分之二以上。
拜登此次加征的301关税,实际上是延续了自2018年7月以来的301关税,顺着中国新能源产业链,从下游到上游,一步一步挤压,逼迫企业将生产环节移出中国,再逼迫企业到美国投资建立产能或转让技术。先堵死新能源汽车整车对美出口,但仍然进口一定规模的用于电动汽车的锂电池,直到这次加税;但对于更上游的天然石墨和永磁体加征25%关税的时间推至2026年;对于主要用于储能的非动力电池从7.5%的301加征关税提高到25%,但实施时间也推迟至2026年,以减少对光伏等新能源发电成本的影响。
针对光伏产品实施高关税的同时,又在301关税复审报告附件中对19种光伏生产设备计划实施临时排除以豁免对其加征关税,从而降低目前在美光伏产品生产企业的成本。
面对拜登政府的本轮加税,中国政府严厉表态将“将采取一切必要措施,捍卫自身权益”。至于具体将采取何种措施,国际观察人士已有不少猜测。比如瑞士经济学家Simon Evenett分析称:虽然这不是一项建议,如果中国针对美国大选中的摇摆州进行贸易限制,其导致的工作岗位损失相当可观,例如在佐治亚州,将导致12139个工作岗位的丧失,这一数字超过拜登在2020年大选时比特朗普多赢得的11779张选票。
当然在在此,我们还不太好预测中国政府将采取何种措施。然而,从近几年我国新能源产业在复杂多变的国际环境中逆势崛起的过程,可以看出基于庞大的国内市场、完整的产业链体系和丰富的高素质劳动力等优势,加速构建双循环新发展格局,以深化改革推动国内统一大市场形成,以扩大开放激发企业全球竞争的活力,这是推动我国新能源产业发展的根本途径。
在遭受将近13年的打压后,我国光伏行业在全球的竞争地位仍然具有绝对优势。如果我们自己的企业练好内功,灵活应变,本轮301关税加征同样也不可能阻挡我国新能源产业持续发展的步伐。

八 |

总体而言,拜登政府此次针对180亿美元产品的加征关税,既有在竞选中和特朗普比狠以争夺选民的目的,也有进一步打压中国新兴产业、争夺新能源产业份额的目的,并非简单的选举做秀。从效果上来判断,这次加征关税对我国出口的边际影响有限,也无法阻挡我国新能源产业的持续发展。但是,拜登政府从下游到上游沿着产业链逐步挤压争夺,先是实质上禁止中国新能源汽车和光伏产品进入美国市场,然后再逐步加严对上游产品的进口限制,其对中国整体新能源产业的中长期影响仍值得我们继续密切跟踪观察。

九 |

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