Human-centered design (HCD) is widely regarded as the best design approach for creating eHealth innovations that align with end users’ needs, wishes, and context and has the potential to impact health care. However, critical reflections on applying HCD within the context of eHealth are lacking. Applying a critical eye to the use of HCD approaches within eHealth, we present and discuss 9 limitations that the current practices of HCD in eHealth innovation often carry. The limitations identified range from limited reach and bias to narrow contextual and temporal focus. Design teams should carefully consider if, how, and when they should involve end users and other stakeholders in the design process and how they can combine their insights with existing knowledge and design skills. Finally, we discuss how a more critical perspective on using HCD in eHealth innovation can move the field forward and offer 3 directions of inspiration to improve our design practices: value-sensitive design, citizen science, and more-than-human design. Although value-sensitive design approaches offer a solution to some of the biased or limited views of traditional HCD approaches, combining a citizen science approach with design inspiration and imagining new futures could widen our view on eHealth innovation. Finally, a more-than-human design approach will allow eHealth solutions to care for both people and the environment. These directions can be seen as starting points that invite and support the field of eHealth innovation to do better and to try and develop more inclusive, fair, and valuable eHealth innovations that will have an impact on health and care. For years, user-centered design (UCD) has been considered to be a crucial part of eHealth design. It is believed to improve an innovation’s usefulness and usability , to imprThe design is based upon explicit understanding of users, tasks, and environments.Users are involved throughout design and development.The design is driven and refined by user-centered evaluation.The process is iterative.The design addresses the whole user experience.The design team includes multidisciplinary skills and perspectives.Meanwhile, in design research as well as in the field of human-computer interaction (HCI), the term UCD has become a topic of much debate. Although the terms UCD and HCD are often used interchangeably, several authors in these fields have argued that the term UCD reduces a person to someone using a technology, failing to see the whole human being that lives with the technology. Gasson , for exaHCD has found its way into eHealth design via several road maps that specifically focus on health and well-being as a domain. The Center for eHealth Research (CeHReS) road map  is perhaMany articles report on the results of HCD processes in eHealth and reflect on the experiences of research and design teams while using the approach  to critically reflect on the concept of HCD. Therefore, before listing the limitations that we would like to stress, we summarize some of the critical reflections on HCD that have been published in the past.In his 2005 essay, “Human-Centered Design Considered Harmful,” Norman  reflectsconsidering the user (and their requirements) and instead, also prioritizes the understanding of people, their concerns, activities, and, in particular, their values and more fundamental needs when designing new technology [community-driven design [In 2011, a study by Bannon  revisitechnology . Forlizzchnology  urges mochnology , Forlizzchnology  also refchnology  identifichnology . More ren design ,35. The n design ,36. The n design -39.These reflections on HCD show that the primary focus on “knowing the end user” is too narrow, and extensions or new approaches have been developed to respond to the need for including additional perspectives and dimensions. Although it incorporates some of the views mentioned previously, this paper specifically focuses on health and well-being as an application domain and the limitations of HCD that we experienced and observed in previous eHealth projects.“It’s not for me, but my neighbor would love this” is what we often hear participants say during design sessions. It makes one wonder, if we always hear this, are we designing something that nobody wants? Or are we talking to the wrong people? HCD methods most often rely on studying a relatively small sample in depth; this approach is prone to a range of sampling biases. By default, we are not talking to the right people, as not everybody can join the sessions; some specific groups will not be represented at all, whereas other groups are overrepresented (a selection bias) . For exaWe would advise design researchers to go further than just naming sampling bias as a limitation in their publication and being done with it. In addition, mapping exactly what the bias looks like  and stating how the neglected groups will be included in the design process  or in the evaluation activities  would be a great improvement.The premise of HCD is that listening to end users and incorporating their needs and wishes into eHealth design will ensure an innovation that end users will want and can use. However, listening to end users  has its limitations. First, a lot of the knowledge, opinions, or attitudes that are crucial for eHealth service design are tacit. Tacit knowledge is developed from direct experience and action and is highly pragmatic, and subconsciously understood . Tacit kend-user input (which can be translated into requirements), but it can also be served by the knowledge and skills of a (multidisciplinary) design team and its creativity, or a by technology push.Consulting the end user early on and throughout the development process of an eHealth service is an important principle of HCD. However, end-user input  is not necessarily the only source of input for designers. The actual design of a service is a creative process that can be fueled by In many articles that describe the HCD process of an eHealth service, end-user input seems to outweigh all the other elements that should inform a thorough design process. We stated in the Introduction section that HCD is part of many (if not most) current eHealth innovation projects. This has created a body of knowledge on user needs and requirements, but this body of knowledge is rarely used to inform other projects. Instead, every project runs its own interview, focus group, and design sessions and the secondary use of end-user input is disregarded. There are some recent exceptions in the field of designing for dementia that resulted in design tools that can, for some part, take over the contextual inquiry phase (such as the MinD toolkit ). These Technology push seems to have become a dirty word in the eHealth community, and user input, translated into requirements, has become the driving force in many eHealth development processes. This preference for end-user input over propagating technological innovations touches upon the classic debate of the technology push versus the demand pull. Can end users imagine what they actually want, or can they only repeat what they have already seen? Even if people are encouraged to imagine functions that they would like to see in a product or service, this may then relate to imagined needs instead of actual user needs. This imposes the risk that these functions are not used in the future [e future . Furthere future . It seeme future .In line with current open science approaches, design (research) teams should make more efforts to make end-user input reusable and to reuse it where possible. Moreover, rather than thinking that end-user input is the only source of inspiration that can lead to value-adding eHealth innovations, they should aim to find the sweet spot where end user consultation, technology push, and the design team’s knowledge and creativity coincide or come together right. Or, as Norman  put it, End users of eHealth solutions are most often patients, care professionals, and citizens, and are crucial in terms of being taken into account when designing a new eHealth service. However, there are also other organizations and actors involved, that is, all stakeholders. Stakeholders can be classified as being either direct or indirect . Direct It is imperative to consult both end users and other stakeholders in order to develop a service model and a business model. A service model is an overview of how a technological service interacts with end users and stakeholders, as well as with any other services (on the web or offline). As such, it is a combination of the patient journey and the care protocol (or care path) envisioned for an eHealth service . A businHolistic design, in which end users (primary and secondary), lead users, and other parties that can exert influence over the implementation and success of an eHealth service are involved, and in which technology, a service model, and a business model are developed simultaneously, is increasingly being used as a successor to HCD. It is at the core of the CeHReS road map, and in recent years, many developers and researchers have reported their experiences with holistic design (and the CeHReS road map) in case studies . HolistIn general, HCD is considered to be a valuable approach that results in better eHealth services, the point of reference here being eHealth services that are developed without user involvement in any form. This is supported by literature claiming, for example, that user involvement was positive overall and through intermediate factors such as better user requirements  or by thSo, how can we make an objective assessment of the value of HCD for the design of eHealth innovations? If we would fall back on the traditional means to assess the quality of an intervention in health care, then the logical thing to do would be to create a single design briefing, give it to one design team that will apply HCD and another design team that will apply an alternative design process that does not include end users directly and evaluate the resulting eHealth services in terms of usefulness, innovativeness, and usability. This way, we would be able to compare whether one approach “performs” better than the other. However, such studies are difficult to perform (as one has to duplicate the design process) and comparing one “condition” with the other is difficult, as there is also creativity and skill involved in design. Controlling for creativity and skill within the comparison among design approaches would be challenging and maybe even impossible. Despite all the challenges involved in setting up a fair comparison between HCD and an alternative approach, Guo et al  conducteThe easiest solution toward “unbiasing” our understanding of the value of HCD in the eHealth context would be to adopt a critical view toward the value of the approach in different case studies even if this comes at the cost of a critical peer review. For example, Kip et al  criticalWhen it comes to developing innovative and disruptive eHealth services, questions posed to prospective end users are naturally going to be hypothetical. So, responses are likely be limited to end users’ ability to envision new concepts (More Than Needs and Wishes section). Although it is the role of the designer to develop new concepts, when we try to understand people’s needs, this is more easily done in the current context and not in the future context for which the design is to be developed. Take the example of developing a technology for the prediction of exacerbations based on real-world data and using these predictions for shared decision-making between patients and professionals. This future scenario is so far removed from the current care setting that it is difficult for people to reflect and articulate associated needs. Sometimes, the future scenario is not very far in the future, but the imagined needs do not necessarily reflect the actual needs when it comes to that specific situation. This was illustrated in the study by Haslwanter et al  in whichAlthough this limitation might be overcome by not relying solely on end-user input, there is also the risk that incorporating end-user input might hamper innovation. Indeed, it might lead to concluding that the status quo is the most desirable future. For example, research related to patients reading their electronic health records showed that health care professionals question the abilities of patients to understand these records and voice concerns which do not necessarily materialize ,72. Herehow we do HCD. In their discussion of designing against the status quo, Khovanskaya et al [In order to move beyond our prejudices and current (working) routines, there are several things we can do, but these require us to change ya et al  offered eventually, while also applying an HCD approach. In this case, however, it is impossible to question potential end users  about this future goal. Their initial standpoint toward a change in behavior may be negative, although at the same time they may have a positive attitude toward caring about (and monitoring) their health. For example, one can probe how one should persuade or support patients with diabetes to be more physically active, but if the participant is unmotivated to do so , every question or probe is likely to result in a negative reply, if not an aversion to the design session in itself, or could lead to a socially accepted reply (not reflecting the participant’s attitude) just to be over and done with the session. The problem here is that the  solution direction of the design team conflicts with the person’s wishes, desires, or values.With the increasing importance of preventing chronic diseases and improving lifestyle in general, many eHealth services aim to change the behavior of end users. They must support people to quit smoking, to sit less, or to eat healthier. This trend has led to a research discipline called persuasive design or design for behavior change. Persuasive design is concerned with developing technology “to reinforce, change or shape attitudes or behaviors, or both, without using coercion or deception”  and has tuning as a paradigm that focuses on building internal self-knowledge and self-awareness by supporting appropriate knowledge, skills, and practice [what end users value but also whether these outcomes ought to be valued.In short, persuasive design and HCD seem to form an unhappy marriage. Therefore, if one were to design a technology that aims to induce health behavior change, one might best trade 1 of the 2 in for something else. Instead of persuasive design, one could resort to using practice . Insteadpractice . In addipractice ) in eHeapractice  are gearpractice . The latpractice . In suchHCD activities focus on individual users, their context, and their needs and expectations in relation to specific tasks and goals. Thus, HCD tends to prioritize the microlevel rather than the mesolevel and macrolevel. However, organizational aspects on the mesolevel are crucial when it comes to the implementation of eHealth solutions in real life . HCD supports the economic and social pillars of sustainability . Howeveropaque (lacking transparency or completely invisible), damaging (harmful or unfair for certain people and creating pernicious feedback loops), or that scale  [Technological advancements such as machine learning and artificial intelligence (AI), have the potential to support people in their everyday tasks . However, they also have the potential to increase inequality by amplifying biases and assumptions that are invisible to users. This has been outlined in the book “Weapons of Math Destruction,” where mathematical models and algorithms are typed as ntially) . Negativntially) . As morentially) . AlthougThese examples show that the human perspective is often not considered or only very narrowly considered for a small user group. The focus on the individual user within an HCD can be complemented by approaches such as VSD, responsible research and innovation , or humaMost eHealth services that are developed through an HCD approach are accompanied by elaborate onboarding procedures and implementation plans. The desire to reach and secure a high number of end users makes sense, as one of the common key performance indicators for these services is the number of end users served (for a longer period). Interestingly, this focus on the first use of the service seems to come at a cost. It rarely happens that a design process also devotes attention and time to longer-term use or to ending the use of a service. Should an app change at some point in the user’s journey? When has an eHealth service fulfilled its purpose? How do we determine this moment? Which actions are associated with ending the end-user journey supported by the eHealth service? It rarely happens that answers to these questions are sought and processed into service design for the eHealth context.A topic that is associated with ending the personal use of the eHealth service is ending the eHealth service completely. It may feel a bit contradictory to think about the terminating of a service during the design stage, but for some services, this will be crucial for acceptance and for preventing undesirable situations. The COVID-19 pandemic has made the need for these deimplementation plans very clear. Contact tracing apps were built on top of the privacy-preserving exposure notification frameworks developed by Google and Apple. Despite the fact that these frameworks did not require tracking the geographical location of end users, they were met with a lot of skepticism and privacy concerns. Indeed, one cannot exclude the possibility that tracking the geographical location by means of this technology might be possible in the future. So although the use of these technologies might be legitimate and useful for the short term, they might be harmful in the long run. Therefore, the introduction of eHealth services that come with large implications, such as the COVID-19 contact tracing apps, should be accompanied by a plan that specifies when we can stop using them and how we can erase all the data that they collect during their lifetime.In this paper, we have described 9 limitations that we currently see with the application of HCD in eHealth. This set of limitations came about by critically reflecting on our own eHealth innovation projects and by reviewing the body of work in this domain. Of course, not all limitations are restricted to the eHealth context and many of them are applicable to the full range of digital services one can develop. However, we felt that it was important to provide a complete overview of the main limitations that we have seen. Again, we would like to emphasize that, even after composing this list of limitations, we do feel that HCD processes have their place in the design of eHealth innovations, especially in combination with other sources of input, such as available knowledge and a technology push. Our objective was to provide a wake-up call to researchers and designers in the eHealth domain. Although some actively seek and implement ways to improve the role of HCD in their innovations, others continue to rely on standard  ways to involve end users. The most important point we want to make is that critical reflection on applying HCD methods in the design of eHealth services is lacking, and this is not helping the field of eHealth innovation to mature. This list of limitations is most probably not conclusive, and we hope that more critical reflection by other researchers in the field will eventually lead to a better understanding of (1) how and when HCD methods can really contribute to the design process (and when they would not do so); (2) how HCD methods can lead to more generalizable knowledge that the field needs and could share; and (3) how HCD methods can be integrated in the process of multidisciplinary design teams that include relevant health, technological, ethical, and other expertise.In addition to the limitations, this paper also discusses several current developments and opportunities to improve the use of HCD in the design of eHealth innovations. This means that there are already signs that the field of eHealth innovation is changing and taking important next steps that change how we see and deal with HCD in eHealth innovation. We briefly want to reflect on and elaborate on 3 of these developments here as we see them as very important for the future of eHealth innovation.In limitations 4, 7, and 8, we have mentioned how VSD or value-based design and also capability sensitive design can provide guidance in involving multiple stakeholders and integrating ethical perspectives in the design process. VSD defines human values as “what is important to people in their lives, with a focus on ethics and morality” . Althougcontributory  to collaborative , cocreation , and extreme citizen science (in which researchers provide tools and methods to enable communities to develop their own participatory research projects) [HCD Risks to Support the Status Quo). As we discuss in limitation 6, in order to envision a new reality, designers or a design team should bring in inspiration, come up with new ideas and imagine new futures, and find ways to introduce and discuss these with the public or the community they are working with. The 10 principles of citizen science, put forward by the European Citizen Science Association in 2015 [In limitation 7, we discussed the problem that in some eHealth development processes, the  solution direction of the design team conflicts with a person’s wishes, desires, or values. Limitation 7 goes on to discuss ways to deal with this situation, but it also triggers the question of whether the solution direction that the design team was aiming for was the right one. Were they trying to answer the wrong question all along? An approach that tries to tackle this is citizen science, which seeks to engage “citizens”  in research in different ways. Citizen science has been around for a while now, and its uptake and importance in health and biomedical research are growing . Citizenrojects) . In the  in 2015 , provideThe Lancet Digital Health stressed this very point [In limitation 8, we discuss how HCD risks missing out on ethical, societal, and political aspects. A prioritization of the microlevel, the personal level, has consequences, especially when this is the preferred and largely dominant approach in a particular field. One such consequence could be that we disregard the impact that our innovations have on the environment. A recent appeal in ry point . In addiry point ,101. As In this paper, we have presented 9 limitations of using HCD in eHealth and 3 directions of inspiration to improve design practices. We feel that these directions provide good starting points to do better and to try and develop more inclusive, fair, and valuable eHealth innovations that will have an impact on health and care. We trust and hope that this discussion of limitations as well as this short outlook to the future of eHealth innovation will stir up a bit of dust and would be very happy to see others add to it so that with more careful, considered, and critical use of HCD we can improve our eHealth research and innovation methods together.


The results showed that SL significantly increased the leaf chlorophyll content from full unfolding to yellowing. However, a remarkable increase in the absorption flux per cross-section (ABS/CS), the quantum yield of electron transport (φEo) and the performance index (PIabs) was observed only in a relatively short period of the leaf life cycle. SL also enhanced the fruit yield and quality. The obviously increased ΔVK and ΔVJ components of the chlorophyll fluorescence induction kinetic (OJIP) curve, along with the significantly decreased PIabs from days 40–60 after unfolding in the SL-treated groups, resulted in more rapid leaf aging and earlier fruit ripening compared with the control plants (CK). Therefore, an energy-friendly SL strategy can alter the physiological status of the PSII apparatus, affecting yield and fruit quality and maturity.The addition of supplemental light (SL) is an effective way to offset insufficient lighting. Although it is commonly believed that SL increases leaf photosynthesis and therefore improves yield and fruit flavor, the mechanism underlying the effects of SL on the photosystem II (PSII) apparatus remains unclear, and SL leads to high energy consumption. In order to save energy, we investigated the physiological status of the PSII apparatus, plant growth parameters and fruit parameters under two types of overhead SL with a low daily energy consumption of 0.0918 kWh m Solanum lycopersicum) is one of the most popular vegetable species in the world, and its year-round production is made possible through greenhouses. To obtain good-tasting fruits and high yields, a daily light integral (DLI) of 20–30 mol m-2 day is suggested [Tomato  in greenhouse production can greatly offset insufficient amounts of light , 5. Heuv2 absorption and assimilation via increased photosynthesis, which ultimately increases yield. SL can also effectively regulate crop growth and accelerate maturity [Previous studies have shown that SL enhances the light absorption of plants as well as COmaturity , 16. Josmaturity  observedmaturity  applied maturity  observed-2 s-1 of red–blue (RB)-LED light (with a daily 10-h photoperiod) to tomato, which increased the yield by 24%, but the electric energy consumption reached 1.2 kWh m-2 day-1. Lu and Mitchell [-2 day-1 of DLI was reported to meet the 25 mol m-2 day-1 DLI requirement of tomato growth between September and December. However, even with a 33% increase in yield, such an SL strategy consumes more than 3 kWh m-2 day-1 [Even with significant benefits, SL is known to consume a relatively large amount of energy. Tewolde et al.  applied Mitchell  suggeste-2 day-1  reported-2 day-1  reported-2 day-1 of energy consumption. We investigated these effects on the physiological status of the photosynthetic apparatus in tomato plants and elucidated its effect mechanism on yield and fruit quality and maturity.The existing strategy in China for overwintering under SL involves the application of a relatively low amount of radiation, with a short daily SL duration of approximately 3–5 h, resulting in low SL energy consumption. To determine the benefit of an energy-friendly SL strategy, this paper investigated an SL strategy involving less than 0.1 kWh m-1, P2O5 content was 536.05 mg kg-1, K2O content was 1161.3 mg kg-1 and organic matter content was 59.49 g kg-1 on October 16. The planting row spacing was 90 cm×45 cm, and the density was 2.5 plants m-2. A total of 5 trusses were left on each plant, and 3, 4, 4, 5, and 5 fruits from the first to 5th trusses, respectively, were kept on the plants, for which harvest began on February 26, 2020 and ended on April 9, 2020. Commercial fertilizers (16-8-34 or 20-20-20 NPK) were applied at 48 kg ha-1 each time, and a total of 241 kg ha-1 was applied in rotation throughout the growing season. The highest temperature in the greenhouse was approximately 28–32°C during the daytime, and the lowest temperature was 8–9°C during the night on sunny days.Seeds of Kaide 6810 tomato  were sown in 50-cell plug trays with substrate consisting of vermiculite, turf soil and perlite (1/1/1) in a greenhouse of the Modern Agriculture Innovation Center  on September 16, 2019. The resulting seedlings were transplanted into soil whose available N content was 311.65 mg kgThe test plot was divided into nine 3.6×6.8 m blocks separated by a hanging perpendicular movable 2.5 m×7 m black nonwoven fabric curtain between blocks to prevent light pollution. Each of the following 3 different treatments was applied to 9 blocks, and each treatment was repeated 3 times in accordance with a randomized block design.T1: Plants exposed to sunlight and SL provided by six overhead 120±5 W HPS lamps in each block.T2: Plants exposed to sunlight and SL provided by six overhead 120±5 W RGB-LED lamps in each block.CK: Plants exposed only to sunlight, without SL.The HPS lamps were obtained from Rongtai Guangyuan Co., Ltd., Henan, China, and the LED lamps with customized emission spectra were obtained from Qilian Technology Co., Ltd., Tianjin, China. The spectra of two types of lamps measured by PLA-20  are shown and described in Figs st day, and then the measurements were repeated on the 10th day, 20th day, 40th day, and 60th day. Before the measurements, the leaflets were clamped into the leaf chamber of the instrument to adapt to the dark for 30 minutes. Then, 3500 μmol m-2 s-1 PPFD of saturated light was applied to determine the OJIP.Chlorophyll fluorescence was analyzed with Handy PEA . For each experimental treatment, the first leaves above the first truss fruit from 10 random plants were measured at the same position and then averaged. The first measurement was performed after most leaves had just completely unfolded and was recorded as the measurement for the 1t) via double normalization to that of the initial level, minimum level (F0) and to the maximum (Fm) level. Taking the Vt of CK at day 1 as the reference (Vt_ref), the ΔVt of the different treatments was calculated via Vt − Vt_ref at the corresponding moment of the induction time, and different ΔVt curves were generated.The intensity of chlorophyll fluorescence was recorded in arbitrary units. Those were transformed into units of the relative variable chlorophyll fluorescence . A positive/negative a* value indicates a reddish/greenish color, while a positive/negative b* value indicates a bluish/yellowish color. Each fruit was measured 4 times in different directions, the a* and b* data were averaged, and the ratio of a*/b* was calculated. The mean a*/b* in each block was used as the indicator of fruit color. At the same time, a field survey was conducted to determine the percentage of fruits at different stages of color change.The tomato ripening stage is distinguished by fruit color. Thus, fruit color was measured 100 days and 110 days after transplanting, when some fruits just began to change color. The first fruits on the first truss from 15 plants were selected randomly in each block, and the color was determined p < 0.05). Based on the ANOVA results, the least significant difference (LSD) test for main comparisons at the 95% confidential level was applied.Microsoft Excel  and SPSS 19.0 were used for statistical analysis and to generate figures. Statistical analysis was performed using one-way ANOVA  curves of the different treatments are shown in A to QB [th day after the leaves fully unfolded, the ΔVK of the SL groups was lower than the ΔVK_ref but it higher than the ΔVK_ref from the 20th day onward /RC are activity parameters used to assess the photosystem II (PSII) apparatus. The SL treatment increased ABS/CS  (ABS) per cross-section (CS) (ABS/CS), ABS/reaction center (RC), RC/CS, and flux of electrons reducing the terminal electron acceptor at the PSI acceptor side (REd ABS/CS . By compeatments . However1 and T2 .Po) of PSII or the maximum PSII efficiency (Fv/Fm) among the three treatments (Eo) was different among the treatments  sensitively reflects changes in the photosynthetic apparatus [abs of T1 reached the highest on the 10th day, and that of T2 and CK peaked on the 20th day after the leaves had fully unfolded. Compared with the highest value in each group, the PIabs decreased by 23.2% and 46.4% in T1, by 12.3% and 47.9% in T2, and by only 4.9% and 33.1% in CK, on the 40th and 60th day, respectively. From the first day to 20th day, the PIabs of T1 was higher than that of the CK, and a significant difference occurred on the 10th day. However, the PIabs of T1 was lower than that of the CK from the 40th day to the 60th day, with no significant difference. The PIabs of T2 was higher than that of the CK from the first day to the 40th day after the leaves had fully unfolded, and a significant difference occurred on the 10th day and the 20th day. On the 60th day, the PIabs of the CK was 10.7% and 6.8% higher than that of the T1 and T2, respectively. Based on analysis of the period from full leaf opening to yellowing, the PIabs of T1 and T2 increased by 7.5% and 15.7%, respectively, in comparison with that of the CK.The performance index of PSII based on absorption . The opposite is observed in low light (20 μmol m−2 s−1). As a result, the value of quantum efficiency of charge separation decreased from 91% in high light to 84% in low light, which showed that the increased light absorption cross section of the large PSII antenna in low light plants came at the cost of decreased charge-separation efficiency. In our study, We also observed that the ABS/RC and RC/CS ratios did not show statistically significant differences between the SL-treated groups and the CK group. However, by comparing the two SL-treated groups, we found a slightly higher ABS/RC ratio in the HPS lamp-treated groups and a slightly higher RC/CS ratio in the LED-treated groups. This might indicate that treatment of plants with HPS-SL increased the light absorption cross section due to a larger antenna size of PSII (higher ABS/RC ratio), but compared with plants treated with LED-SL which perhaps have a smaller antenna size and a faster overall PSII trapping time due to higher RC/CS ratio, the quantum yield of electron transport (φEo) in plants treated with HPS light was downregulated by approximately 1.2%. The RE0/RC ratio of the young leaves (1–20 days after leaf unfolding) in the SL-treated groups did not show a significant difference from that in the CK group but was significantly lower than that in the CK on the 40th day  –35. Wien40th day . At the 0th days , which io stress , 36.-2 day-1. The Fv/Fm ratio did not differ substantially between the SL-treated groups and the CK group. However, the Pn of the leaves, especially in the intracanopy LED- and hybrid-treated groups, was significantly higher than that in the CK, and the yield increased by 33%. In our study, the Fv/Fm (=φPo) value between the SL-treated groups and the CK group was also not significantly different from when the leaves were fully unfolded to when they turned yellow. The φEo and PIabs values of the LED-treated group were the highest, followed by those in the HPS lamp-treated group and the CK group. Therefore, based on the performance of the photosynthetic apparatus, we conclude that the SL treatment improved the ABS/CS, φEo and PIabs values of the leaves, which increased the photosynthetic capacity accordingly, and enhanced the yield and fruit quality. The increase in fruit fresh weight and amount of supplemental lighting showed a positive linear relationship [Gómez and Mitchell  applied tionship . In the tionship  reportedtionship  applied tionship  used a Lv/Fm ratio, the PIabs can more precisely reflect the state of the photosynthetic apparatus. This study showed that the plants in the groups treated with SL presented their maximal PIabs value earlier than plants in the CK group, which implies that SL accelerated the formation of the PSII apparatus. Dueck et al. [abs of leaves grown under HPS lamp dropped rapidly from the 20th day on after unfolding, but that this rapid drop in the LED-treated group occurred from the 40th to 60th day, which was more obvious than that in the CK in leaves of the same age  and shortening the photoperiod of SL (3 h day-1), therefore, the energy consumption required for the SL is relatively low (<0.1 kWh m-2 day-1). However, this treatment promotes the performance of the leaf photosynthetic apparatus, promotes plant growth and increases yield. Although the yield and fruit quality obtained via the LED SL strategy is better than that resulting from the HPS-SL strategy, it is desirable for the fruit to change color and for maturity to occur 10 days earlier, as observed in plants grown under HPS-SL compared with plants grown under LED SL.Compared with the SL strategies used in other studies, our strategy involves reducing the number of light sources Click here for additional data file.


In the range of used MnO4− , corrosion behaviour is examined with regard to hydrogen evolution and composition (protective barrier properties) of forming corrosion products. The corrosion behaviour of HDG samples is evaluated using Rp/Ecorr and EIS. The composition of corrosion products is evaluated using SEM, XRD, XPS and AAS. The effective MnO4− ion concentration to prevent the corrosion of coating with hydrogen evolution is 10−3 mol·L−1; lower concentrations only prolong the time to passivation (corrosion with hydrogen evolution). The highest used MnO4− concentration ensures corrosion behaviour without hydrogen evolution but also leads to the formation of less-protective amorphous corrosion products rich in MnII/MnIII phases.This paper evaluates the amount of KMnO The use of coatings in the protection of conventional concrete reinforcement can provide effective means of prolonging the service life of reinforced structures ,2. The rThese initial concurrent corrosion reactions significantly limit the use of hot-dip galvanized rebar for concrete reinforcement. Anodic corrosion reaction reduces the coating thickness, and cathodic reaction (hydrogen evolution) increases the porosity of the cement paste at phase interface. This increase in porosity can reduce the bond strength between coated rebar and concrete ,12,13,143]2·2H2O  2·2H2O and compounds with Mn in different oxidation states.This paper studies the effect of MnOed above  does not2. Prior to hot-dip galvanizing, the samples were  degreased in 10 wt. % NaOH and pickled in 12 wt. % HCl solution. After pickling, the samples were rinsed in multiple steps . During the hot-dip galvanizing process in the automatic coating line, the samples were again pretreated in alkaline degreasing solution  and pickled in 7–12 wt. % HCl solution . After coating, the samples were cooled in ambient air.For the sample production, flat carbon steel sheets of 40 mm width were used. The composition is shown in 4 were produced ) 2·2H2O which strongly inhibits the corrosion damage to the HDG steel in this environment [2 by filling the pores between Ca[Zn(OH)3]2·2H2O) 2·2H2O) ,21.p/Ecorr trend of HDG samples in simulated concrete pore solution (pH 12.8) with addition of only 10−4 mol·L−1 KMnO4 (Mn(1)) is very similar to the trend in solution without any KMnO4 (ref). Nevertheless, the time to the passivation of HDG samples is slightly  increased. The total time of coating corrosion with hydrogen evolution is similar to or even longer than that for samples exposed in simulated concrete pore solution without any addition of KMnO4. The effect of MnO4− on precipitation of common corrosion products 2) is not apparent from Ecorr trend; however, Rp is about 20 % lower past 120 h compared to reference solution, suggesting that the corrosion products might be altered. It is feasible that this solution allows competing cathodic reactions of reduction MnO4− or MnO4(−2) to, for example, MnO2. The reduction of MnO4− to MnO4(−2) in an alkaline environment (3) proceeds relatively quickly  − 1, where α takes values in range 0 to 1. Values close to 0 correspond to the behavior of the resistor and values close to 1 to the capacitor.To provide a more fundamental understanding of the electrochemical mechanism of corrosion of HDG in simulated concrete pore solutions with KMnOMeasurements of EIS for individual solutions is shown in 4, a rapid drop in R ref (ct) is observed initially, suggesting oxidized surface of HDG (higher content of ZnO/Zn(OH)2 2·2H2O (CHZ) and ZnO 2·2H2O decreases. After exposure in Mn(3), CHZ was not detected at all. The analysis also showed the presence of ZnO in corrosion products (not the Zn(OH)2), even after exposure in solution with highest concentration of MnO4−. Obviously, Mn-based corrosion products  are amorphous 2·2H2O. According to 4 in concentration of 10−4 mol·L−1 (Mn(1)) does not result in precipitation of phases with significant content of manganese.Corrosion products from HDG samples from individual exposure were removed using a solution of hydrochloric acid, and the contents of calcium and manganese in the solution was analyzed. The results for all simulated concrete pore solutions are shown in the bar chart in DG steel ,117,127.4− is typical for the formation of less-protective corrosion products and fundamental changes in the corrosion mechanism of HDG.The highest concentration of MnO4 as a corrosion inhibitor of hot-dip galvanized reinforcement (preventing coating corrosion under the development of hydrogen and at the same time limiting anodic corrosion reaction) cannot be carried out without the clarification of the influence of MnO4− anions on the hydration of cement and resistance of the resulting concretes to climatic influences . It is clear from the literature that the contamination of developed concretes with metal oxides such as ZnO 2·2H2O, ZnO/Zn(OH)2). Contrarily, at lowest MnO4− concentrations (10−4 mol·L−1) there are no significant changes in the corrosion mechanism of hot-dip galvanized steel, that is the corrosion occurs with hydrogen evolution and the anodic process is uninhibited. At this concentration, normal formation of the zinc corrosion product layer 2) is hindered and the time period of HDG corrosion with hydrogen evolution is prolonged. At the highest MnO4− concentration, a significant reduction of corrosion takes place due to the inhibition of the charge transfer reaction (without hydrogen evolution). Nevertheless, a low-protective layer of corrosion products is formed with minimal content of zinc compounds.Based on exposures in simulated concrete pore solutions of pH 12.8 with added . Lower concentrations can prolong the corrosion of HDG steel with a high rate of hydrogen evolution. While high concentrations of MnO4− ensure low corrosion rate and prevent hydrogen evolution, they also result in the formation of less-protective layers of corrosion products. This phenomenon can have a negative effect on the protective capabilities of HDG steel against chloride anions. For these reasons, the use of KMnO4 in real conditions of large concrete constructions would require the strict observance of the optimal dosage of this substance into the concrete mixture and at the same time prolonging the time of its homogenization (thorough mixing). The application of this inhibitor to concrete mixes during the construction of structures using hot-dip galvanized reinforcement would probably not have been possible without thorough control operations of the composition of the individual concrete mixes.The effective use of KMnO4− ions for reinforced concrete structures with implemented hot-dip galvanized reinforcement, it is necessary to verify their inhibitory effect in case of concrete contamination by supercritical amounts of chloride anions from de-icing salts .For the practical use of MnO4 addition to cement mixtures make the application very problematic, since it can be released into environment.Environmental aspects of KMnO4 but with a broader interval of effective concentration. These compounds also need to be environmentally-friendly and non-toxic to humans.Further research must focus on the use of corrosion inhibitors with similar effects to those of KMnO


A two-sided P value < 0.05 was considered statistically significant. A total of 17 eligible non-randomized trials with 455 participants were included into analysis. The most common primary endpoint was pCR , and the median sample size and follow-up period was 23 patients and 7.9 months, respectively. For patients receiving neoadjuvant immunotherapy, the overall pCR, R0 resection, and grade 3-4 AE rates were 33.2%, 95.5%, and 35.1%, respectively. For esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EAC), neoadjuvant immunochemoradiotherapy showed no significant improvement in pCR rate than NCRT . Grade 3-4 AEs were the most common in patients with neoadjuvant immunochemoradiotherapy, significantly higher than immunochemotherapy  and NCRT . In conclusion, for patients with resectable esophageal or GEJ carcinoma, the addition of ICIs to standard NCRT could not improve pCR rate in both ESCC and EAC, but significantly increased the risk of severe AEs. Large-scale phase 3 randomized trials were urgently needed to further confirm the survival benefit and safety profile of neoadjuvant immunotherapy.Neoadjuvant chemoradiotherapy (NCRT) plus radical esophagectomy is currently the standard treatment for resectable esophageal or gastroesophageal junction (GEJ) carcinoma. The aim of this study is to evaluate the efficacy and safety of neoadjuvant immunotherapy in resectable esophageal or GEJ carcinoma. Prospective clinical trials investigating efficacy and/or safety of neoadjuvant immunotherapy with immune checkpoint inhibitors (ICIs) followed by radical esophagectomy in patients with newly diagnosed resectable esophageal or GEJ carcinoma were identified through literature search. Quality assessment was performed by using the Newcastle–Ottawa scale. Preliminary treatment outcomes of pathologically complete response  and grade 3-4 adverse effects (AEs) were pooled together and then compared with standard NCRT of the historical control CROSS study by Chi-square (χ Esophageal or gastroesophageal junction (GEJ) carcinoma is the sixth most common cancer-related cause of death worldwide, with an estimated 500,000 deaths annually . CurrentImmune checkpoint inhibitors (ICIs), as a monotherapy or in various combinations, have revolutionized anti-cancer therapy in many solid tumors. For advanced/metastatic esophageal or GEJ carcinoma, programmed cell death receptor 1 (PD-1) inhibitors pembrolizumab and nivolumab have significantly prolonged survival than conventional chemotherapy regimens –7. In thIn this study, we performed a pooled analysis of prospective clinical trials of resectable esophageal or GEJ carcinoma treated with neoadjuvant immunotherapy. The primary purpose of this study is to compare the efficacy and safety of neoadjuvant immunotherapy with standard NCRT.This study was exempted from review by the institutional review board because it only collected published data, and no human subjects were newly enrolled. This study included prospective clinical trials investigating efficacy and/or safety of neoadjuvant immunotherapy with ICIs followed by radical esophagectomy in patients with newly diagnosed resectable esophageal or GEJ carcinoma. Studies were excluded if they met any of the followings: retrospective cohort study, inoperable patients, previously treated patients, conventional neoadjuvant chemotherapy/radiotherapy, inadequate report on efficacy and safety, non-epithelial histology , or non-English publication.Clinical trials published before June 2022 were identified through a systematic literature search of Embase, PubMed, Web of Science, and the Cochrane Library by using the following search terms:  AND (“neoadjuvant” or “preoperative”) AND , with article type restricted to prospective study. A manual search on article references and abstracts of American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) annual meetings was also performed to include potentially eligible studies. The literature search and study inclusion were independently conducted by JZ and BG, and disagreements were further resolved by the consensus of JZ, BG, and QW.https://www.clinicaltrials.gov).For non-randomized trials or cohort studies, quality was assessed with a maximum 9-star score, by using the Newcastle–Ottawa scale (NOS) in terms of selection, comparability, and outcome . Trials The primary endpoint pCR was defined as no residual cancer cells in both tumor and lymph node (ypT0N0). R0 resection was defined as no cancer cells at resection margins microscopically. Adverse effects (AEs) were graded according to the criteria of original studies, mostly the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE).Data including trial phase, pathological type, primary endpoint, median follow-up time, sample size, neoadjuvant treatment regimen, pCR rate, R0 resection rate, grade 3-4 AE rate, and CTCAE version were extracted.2, once a week for 5 weeks), and radiotherapy  , paclitaxel (50 mg/m a week) –11, 14.2) test was used to compare treatment outcomes between different neoadjuvant treatment regimens. Subgroup analysis was conducted to investigate the efficacy and safety of different chemotherapy schemes. To assess the consistency and robustness of the overall efficacy and safety across different settings, sensitivity analysis was performed by leaving each trial out at a time. Statistical analysis was performed by SPSS statistical software . A two-sided P value < 0.05 was considered statistically significant.Overall efficacy and safety were calculated after pooling results of all trials. Chi-square , with no RCTs included. The most common primary endpoint was pCR , followed by safety , feasibility , and MPR . The median sample size and follow-up period was 23 patients and 7.9 months, respectively. There were 104 (21%) and 351 (77%) participants receiving neoadjuvant immunochemoradiotherapy and immunochemotherapy, respectively. There were 399 (88%) and 56 (12%) patients with the pathological type of esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC), respectively. For all patients receiving neoadjuvant immunotherapy, the overall pCR, R0 resection, and grade 3-4 AE rates were 33.2%, 95.5%, and 35.1%, respectively.P = 0.9), but demonstrated a significantly higher pCR rate than immunochemotherapy . A significantly lower pCR rate in ESCC was observed after neoadjuvant immunochemotherapy than NCRT  (P = 0.22) (P = 0.1). Sensitivity analysis of 13 trials receiving neoadjuvant immunochemotherapy demonstrated acceptable consistency with no significant differences in overall pCR and R0 resection rate (P > 0.05)  Figure 2P = 0.04) and NCRT  (P > 0.05) , 7 (41%), and 3 (18%) trials applied CTCAE v4.03, CTCAE v5.0, and unknown criteria, respectively. The historical control CROSS study adopted CTCAE v3.0. Grade 3-4 AEs were the most common in patients with neoadjuvant immunochemoradiotherapy, significantly higher than immunochemotherapy  Figure 2 0.0001) . SensitiP = 0.06) and grade 3-4 AEs  than neoadjuvant immunochemotherapy with TC scheme. With the cost of significantly increased grade 3-4 AEs , neoadjuvant immunochemotherapy with TC scheme failed to show a superior pCR outcome than CROSS trial . For trials with neoadjuvant immunochemotherapy of cisplatin-based regimens in ESCC, overall pCR, R0 resection, and grade 3-4 AE rates were 25.8%, 97.9%, and 24%, respectively. The cisplatin-based regimens exhibited superior safety than TC regimen in neoadjuvant immunochemotherapy .In subgroup analysis of neoadjuvant immunochemotherapy in ESCC, trials with chemotherapy regimen paclitaxel or nab-paclitaxel plus carboplatin, every 3 weeks (TC scheme) were included. Overall pCR, R0 resection, and grade 3-4 AE rates were 34.8%, 93.2%, and 37.3%, respectively. Neoadjuvant immunochemoradiotherapy demonstrated no significant improvement in pCR rate (50% vs 34.8%, This pooled analysis enrolling qualified prospective trials of resectable esophageal or GEJ carcinoma treated with neoadjuvant immunotherapy indicated that preoperative addition of ICIs to standard NCRT could increase the risk of severe AEs, however, without significant improvement in pCR. These findings provided more objective and comprehensive efficacy and safety evaluation of neoadjuvant immunotherapy than single small-scale trial, which could help with precise sample size calculation in future trials and accelerate the process of phase 3 RCTs.A recently published real-world multicenter retrospective study in China which mainly included patients with locally advanced ESCC reported a pCR rate of 42.3% and 25.5% after neoadjuvant immunochemoradiotherapy and immunochemotherapy, respectively, which was approximative to the prospective outcomes in this study . In stanFor safety, it should be cautious that the addition of ICIs to NCRT could increase the risk of severe even lethal complications. Compared with this pooled analysis of trials, grade 3-4 AEs were less frequently reported in the real-world practice, with 23.3% and 12.7% in neoadjuvant immunochemoradiotherapy and immunochemotherapy, respectively . HoweverThere were some limitations in this study. First, this is a literature-based pooled analysis with individual patient data unavailable, thus patient-level safety profile was absent. The report on AE in this study was mainly about incidence, not comprehensive safety profile. Patient-level safety profile should be comprehensively evaluated in further research by using individual patient data. Second, the follow-up time of enrolled trials was not long enough for adequate report on long-term survival, and the survival benefit was unable to evaluate in this study. Third, from 2006 to 2017, the CTCAE criteria were evolved from v3.0 to v5.0. CTCAE v3.0 mainly assessed objective tissue damage and clinical examinations. CTCAE v4.03 further evaluated symptoms and functional abnormalities additionally, and showed advantages over v3.0 in delegating quality of life. Compared with CTCAE v4.03, v5.0 mainly updated 54 algorithms in 19 lab parameters, with few changes in grade criteria. The heterogeneity in AE assessment existed and could not be removed in this study.In conclusion, for patients with resectable esophageal or GEJ carcinoma, the addition of ICIs to standard NCRT could not improve pCR rate in both pathological types ESCC and EAC, but significantly increased the risk of severe AEs. Large-scale phase 3 randomized trials were urgently needed to further confirm the long-term survival benefit of neoadjuvant immunotherapy.The original contributions presented in the study are included in the article/Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements.QW, YH, and LP designed the study and revised the manuscript. JZ collected raw data, performed statistical analysis, and drafted the manuscript. JZ and BG performed literature search. XL, BW, LW, HZ, JM, and YT collected raw data. All authors contributed to the article and approved the submitted version.


Antimicrobial prescription in critically ill patients represents a complex challenge due to the difficult balance between infection treatment and toxicity prevention. Underexposure to antibiotics and therapeutic failure or, conversely, drug overexposure and toxicity may both contribute to a worse prognosis. Moreover, changes in organ perfusion and dysfunction often lead to unpredictable pharmacokinetics. In critically ill patients, interindividual and intraindividual real-time β-lactam antibiotic dose adjustments according to the patient’s condition are critical. The continuous infusion of β-lactams and the therapeutic monitoring of their concentration have both been proposed to improve their efficacy, but strong data to support their use are still lacking. The knowledge of the pharmacokinetic/pharmacodynamic targets is poor and is mostly based on observational data. In patients with renal or hepatic failure, selecting the right dose is even more tricky due to changes in drug clearance, distribution, and the use of extracorporeal circuits. Intermittent usage may further increase the dosing conundrum. Recent data have emerged linking overexposure to β-lactams to central nervous system toxicity, mitochondrial recovery delay, and microbiome changes. In addition, it is well recognized that β-lactam exposure facilitates resistance selection and that correct dosing can help to overcome it. In this review, we discuss recent data regarding real-time β-lactam antibiotic dose adjustment, options in special populations, and the impacts on mitochondria and the microbiome. Treatment prescription in critically ill patients represents a complex challenge, as drug dosing might be a game changer for the progression towards organ failure or death. On the other hand, changes in organ perfusion and function lead to unpredictable pharmacokinetics and side effects. In the end, adequate dosing in critically ill patients may be especially difficult to achieve .Antibiotics are among the most used drugs in critically ill patients, and β-lactams are considered the most useful class among them . The oveAchieving the rapid killing of bacteria responsible for infections is of the utmost importance to resolving infection and sepsis . HoweverAccordingly, the doses of antibiotics can no longer be seen as fixed from the beginning to the end of treatment, and real-time adjustments to the patient’s condition are critical. The continuous infusion of β-lactams  and the In patients with renal or hepatic failure, adequate dosing of antibiotics can be even more challenging because not only is clearance decreased but adaptative changes may also influence drug concentration and distribution . ExtracoIncreasing the dose to achieve adequate bacteria killing is tempting, especially in septic shock patients. However, recent data have emerged linking overexposure to β-lactams to undesired effects, especially targeting the central nervous system , mitochoMost reviews on this subject have focused on using high doses to achieve increased bacterial clearance. However, concerns about overexposure and toxicity should also be addressed.In this narrative review, we aim to discuss the challenges of β-lactam dosing, focusing not only on efficacy but also on the prevention of toxicity and the emergence of resistance. The need to address intra- as well as interpatient PK variability, namely promoting personalized dosing, is also discussed.Critically ill patients commonly present significant pathophysiological changes that modify the PK of antimicrobials . ParticuThese changes, noted in sepsis, result from a significant fluid shift from the intravascular compartment to the interstitial space . These sThe antibiotics’ volume of distribution (Vd) is often increased ,25, and The β-lactams’ Vd is also influenced by protein-binding modifications , particuNot only do these pathophysiological changes directly influence antibiotic concentrations, but therapeutic interventions can also cause dramatic modifications of the antibiotic PK . InvasivAcute kidney injury and a reduced glomerular filtration rate  are alsoEven in patients without acute kidney injury, the antibiotics’ serum concentrations may be severally altered due to augmented renal clearance ,31. ThisThese PK changes are dynamic, and daily changes are very common, leading to the frequent need to adapt the antibiotic dosage. Antibiotic concentrations can be quite unpredictable, and failure or toxicity, which are directly related to a change in the concentration, may become frequent .Furthermore, the relationship between the amount of drug being administered and the time of perfusion, either by conventional intermittent dosing or extended or continuous infusion, may influence its PK.β-lactam antibiotics act through a pathway that blocks the growth and replication of bacteria, leading to their death. Their main mechanism of action is the inactivation of enzymes located in the bacterial cell membrane, known as penicillin-binding proteins, which are involved in cell wall synthesis . It is wAlthough all β-lactams share the same β-lactam ring, they present different structures and bacteria-sensitive profiles, leading to their classification in different classes, namely penicillins, cephalosporins, monobactams, and carbapenems ,36. ThesThese antibiotics are time-dependent, that is, their activity is mainly related to the time their concentration is above the minimal inhibitory concentration (MIC). Different thresholds have been determined for the diverse classes of β-lactams in vitro or in animal models . BacteriThe concept of dose modulation consists of a broader and more innovative view of de-escalation. This includes the front-line variability in the antibiotic dosage, according to patient and microorganism characteristics, followed by its reduction after clinical response and patient recovery. This means concentrating the largest weight of antibiotics at the front end , when thIn fact, in patients responding to therapy and recovering from infection, there is commonly a hemodynamic improvement, with the weaning of vasopressors, a negative fluid balance, and the normalization of cardiac, renal, and hepatic functions, which also lead to progressive antibiotic PK normalization .Therefore, after hemodynamic recovery, if the patient is improving and there is evidence of a clinical response, it is probably safe to reduce the antibiotic dose to reduce the risk of antibiotic toxicity. Furthermore, there is a large amount of evidence that the duration of antibiotic treatment can be largely decreased ,42, whicThis strategy, along with the use of a broad-spectrum combination antibiotic therapy, may help to overcome the limitations to its efficacy posed by the large inoculum , the PK Conventional antibiotic dosing, accounting only for changes in renal or hepatic clearance, may be prone to failure in complex critically ill patients .In fact, despite the PK changes, the dose is usually maintained throughout the treatment course. With an expanding knowledge of the relationships between antimicrobial dosing, pharmacokinetic/pharmacodynamic (PK/PD) exposure, and patient outcomes , there iAs already pointed out, antibiotic dosing in critically ill patients is especially challenging due to the increased Vd  and the Therefore, TDM for β-lactams has been suggested for routine implementation in the treatment of critical illness. Accordingly, TDM would help to implement the dose modulation strategy, facilitating the early attainment of the maximal tolerable dose  of the sThe most conventional and practical method to use TDM is based on the evaluation of a single PK sampling at the end of a dosing interval . The measured serum concentration is compared against a therapeutic target range, and dosage adjustments are performed. This constitutes the easiest methodology, but it is also the least accurate for dosing adjustments. Limited sampling strategies incorporate up to three samples, providing more informative concentration time points for PK description ,47. ThesfT > MIC) or even more than four times above that target . To. To49]. Patients with chronic renal or hepatic dysfunction must be treated based on the same principles that were previously mentioned, regardless of pre-existing dysfunction: initial dosing according to the estimated level of drug Vd and maintenance therapy guided by organ dysfunction .Acute kidney injury is a common sepsis-induced organ dysfunction that is associated with an increased risk of death and a longer length of hospital stay . β-lactaIn a retrospective study of septic patients, Taccone et al. noted that, despite the use of an initial loading dose independent of organ dysfunction, most of the patients had suboptimal concentrations after their first dose of β-lactams, ranging between 16% (cefepime) and 75% (meropenem) . To ensuIn septic patients with acute kidney injury, the evaluation of creatinine clearance is challenging due to variations in fluid balance, kidney function fluctuations, and creatinine metabolism  since seThe dosing of β-lactam antibiotics in patients supported with renal replacement therapy remains unclear. There is a wide range of renal replacement therapy characteristics that make the optimal antibiotic prescription difficult in the intensive care unit, such as the modality heterogeneity  and the prescribed filter types and settings  ,72.In critically ill patients with acute kidney injury, the β-lactam doses defined for stable chronic renal failure patients may lead to underdosing . On the In the largest published pharmacokinetic study in critically ill patients receiving renal replacement therapy, a considerable variation in antibiotic dosing administration was noted . No consThe effect of liver dysfunction on β-lactam concentrations is less well defined. Despite the liver’s strong impact on the elimination of lipophilic drugs, it may also influence the clearance of hydrophilic drugs. Patients with liver disease often have decreased renal clearance, even with normal serum creatinine. Thus, a dose reduction may be necessary, even for kidney-cleared antibiotics .Hypoalbuminemia, resulting from the decreased hepatic synthesis and capillary leakage, contributes to an increase in Vd and the clearance of highly protein-bound antibiotics, namely ceftriaxone, ertapenem, and flucloxacillin . These pData on PK during extracorporeal circulation to support severe hepatic failure are scarce.Antibiotic PK during ECMO support is affected by drug sequestration in the surface area of the tubing and membranes (again associated with an increase in the Vd), which is potentiated by the age of the circuit and reduced regional kidney and liver blood flows (reducing drug clearance) ,82.p = 0.21) [p = 0.18), and this correlated with the creatinine clearance and the presence of renal replacement therapy, suggesting a role of creatinine clearance in guiding the maintenance dose [Shekar et al. compared the PK of meropenem in septic patients receiving or not receiving ECMO support. They found that the Vd of meropenem was not significantly higher in the ECMO group compared to the controls  . Consequnce dose . A subsence dose . In opponce dose . The autnce dose .Still, data concerning PK and antibiotic dosing in ECMO are scarce and came from small single-center and neonate studies , making fT > MIC and 100% fT > 4 × MIC) was poor, but there was no difference between the ECMO and matched control patients [A recent study addressing meropenem PK included 14 patients on ECMO matched to 11 controls. The attainment of PK/PD targets . [Acute kidney injury due to acute interstitial nephritis is more frequent with some β-lactams such as piperacillin/tazobactam, although it has also been reported with amoxicillin . This co 0.032). .Even more frequent than acute kidney injury are encephalopathy and neurological toxicity . There aThe mitochondrial toxicity of antibiotics has been known for a long time and might partially explain renal, ontological, and neurologic toxicity . This efIn 1990, using an animal model and in vitro studies, Tune et al. suggested that imipenem and a cephalosporin could induce, in a dose-dependent manner, irreversible changes in the kidney tubular function through the direct impairment of mitochondrial function . More reThe hepatic cytotoxicity of amoxicillin/clavulanate can also be partially attributed to mitochondrial dysfunction due to direct mitochondrial membrane breakdown, leading to the expulsion of cytochrome C, lipid peroxidation, and a decrease in the energy content , especiaMost of the data related to the effects of antibiotics on the microbiome and its association with disease status come from preclinical studies. For instance, animal studies have suggested a direct association between antibiotics, the loss of microbiome diversity, gut epithelial changes, and impaired mucosal IgA . In addiData on the antibiotic disruptions of the human microbiome in different pathologies and antibiotic-induced dysbiosis are also being gathered. It is also important to recognize that the microbiome shapes not only global health but also the metabolism of drugs and the response to treatments . In contSeparate parts of the human body harbor different microbiomes, including the skin, mouth, and lungs, which are all affected by antibiotics, although it is the microbiome of the gut (the most abundant and diverse) that is more prone to antibiotic-induced changes.The effect of broad-spectrum antibiotics on the lung microbiome and its association with ventilator-induced injury were recently reviewed by Siwicki-Gieroba . The samOne of the most frequent side effects of antibiotics is diarrhea. In a recent study involving 66 children with community-acquired pneumonia, the development of diarrhea was evaluated longitudinally and was associated with the dysbiosis of the microbiome . This dyThe use of antibiotics is commonly known to facilitate the emergence of resistance. It occurs both through the selection of resistant bacteria, usually in the gut , that caNevertheless, this proliferation of a specific phenotype that is able to resist the antibiotic insult comes with a metabolic cost. Resistance to antibiotics often implies changes in bacterial targets, that is, bacterial cell structures associated with the maximum efficacy to survive. These changes can impose a fitness cost on the bacterium when the antibiotic insult stops , which mAccordingly, the evolutionary advantage of the mutation or plasmid expression associated with the repeated use of antibiotics may also be associated with an equal fitness cost, and the wild-type susceptible bacteria often will outcompete resistant strains in a different environment after antibiotic administration has ended or in the community.However, repeated mutations during prolonged antibiotic exposure may lead to a compensatory evolution where a mutation combination contributes to the recovery of fitness by specific bacterial clones . These wResistant clones of bacteria such as Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecium, Pseudomonas aeruginosa, and even Streptococcus pneumoniae can easily survive in the community, even without known antibiotic exposure.The selection of antibiotic doses has been proposed as a strategy to prevent the emergence of resistance. This implies the consideration of the pharmacokinetic and pharmacodynamic properties and the possible use of antibiotic combinations . In addiThe suppression of resistance has been proposed to be related to higher antibiotic concentrations than those associated with efficacy. For β-lactams, the proposed best PK/PD index that decreases the emergence of resistance in Gram-negative bacteria is MIC ≥ 4 . Still, Theoretically, a higher antibiotic concentration should be able not only to suppress wild-type (sensible) bacteria but also mutants, with a higher MIC. This has been conceptualized in the mutant prevention concentration theory, which supports the use of drug concentrations above the lowest antibiotic concentration that prevents the replication of the least susceptible single-step mutant ,122,123.Although appealing, this mutant selection window hypothesis would depend on the ability to completely suppress the mutant clone to prevent it from proliferating and becoming dominant without competition. Although this complete suppression may seem appealing in vitro , it is pConsequently, achieving this higher target antibiotic concentration can reduce the total burden of bacteria, but it can also, paradoxically, facilitate the proliferation of the mutant single-step clone, which may lead to reduced antibiotic susceptibility. High doses of antibiotics foster opposing processes involving mutation-resistant strains and their release from the ecological competition . WhetherAn ideal antibiotic dosing regimen should, consequently, maximize bacterial cell killing while minimizing drug toxicity and the risk of resistance development throughout the antibiotic treatment duration . A dose Overall, antimicrobial use in clinical practice has several caveats, and quality programs to solve them are challenging. Antimicrobial stewardship programs are now implemented in most modern hospitals, and they must consider not only the indication for a given antibiotic according to the patient infection and severity but also the unintended consequences of their usage in each setting, both for the patient and the environment. β-lactams’ unrestricted use has already led to the development of panresistant microbes, such as panresistant Pseudomonas aeruginosa and Klebsiella pneumonia. Outbreaks of such bugs in hospital settings, particularly in intensive care units and hematological or surgical wards, are especially cumbersome. In addition, there are already reports of panresistant microbes in community settings, which, together with hospital dissemination, present significant biosafety issues .In the future, the challenge will be to develop new drugs against panresistant bacteria  with no Overall, these challenges should not restrain the development of new drugs or their introduction into clinical practice, as recommended in recent years by the World Health Organization .In recent years, β-lactam PK have largely been unveiled, and improved dosing is now possible. Unfortunately, dosing strategies to achieve specific therapeutic targets (measured by the PK/PD relationship) have produced conflicting results. Moreover, although the TDM of β-lactams remains attractive, the clinical benefits are still unproven. We believe that this is due to a lack of understanding of the real PK/PD targets. For TDM to be beneficial, there must be a clear relationship between the drug concentration and the intended effect. That is probably not the case with β-lactam antibiotics, as differences according to the infection itself, the bacteria, and the host may all lead to different therapeutic targets.During the last few years, there has been a greater understanding of the potential adverse effects of β-lactams. These effects are not only related to an increase in bacterial resistance  but also to toxicity to the patients, organ injury, and ultrastructural cellular changes, especially in the mitochondria. A greater understanding of the role of the microbiome has contributed to understanding the collateral damage of antibiotics.We believe that future studies should focus on the measurement of antibiotic PD, namely quantifying the death of bacteria as well as antibiotic concentrations and potential toxicity, using tests that allow rapid turnaround results for clinicians. This should also provide support for an even further reduction in antibiotic duration. Ideally, antibiotic therapy should be personalized to address the unique host–bacteria relationship and to overcome the bacteria’s virulence.Studies on non-antibiotic approaches will likewise enlarge our therapeutic options. Replacing the microbiome and preventing the emergence of resistance should also be goals for therapy in the next few years.


Tailored nano‐spaces can control enantioselective adsorption and molecular motion. We report on the spontaneous assembly of a dynamic system—a rigid kagome network with each pore occupied by a guest molecule—employing solely 2,6‐bis(1H‐pyrazol‐1‐yl)pyridine‐4‐carboxylic acid on Ag(111). The network cavity snugly hosts the chemically modified guest, bestows enantiomorphic adsorption and allows selective rotational motions. Temperature‐dependent scanning tunnelling microscopy studies revealed distinct anchoring orientations of the guest unit switching with a 0.95 eV thermal barrier. H‐bonding between the guest and the host transiently stabilises the rotating guest, as the flapper on a raffle wheel. Density functional theory investigations unravel the detailed molecular pirouette of the guest and how the energy landscape is determined by H‐bond formation and breakage. The origin of the guest's enantiodirected, dynamic anchoring lies in the specific interplay of the kagome network and the silver surface. A kagome network on the Ag(111) surface hosts guest molecules with enantiomeric selectivity. Each larger pore confines a single guest molecule. The punctuated pirouette of the guest molecule in this confined space is unravelled by a combination of density functional theory and variable temperature scanning tunnelling microscopy in real time at the single molecule level. Inspired by biomolecular rotors that are omnipresent in nature, artificial molecular rotors have drawn attention in the field of nanoscience due to their potential application as functional molecular nanomachines. Mounting such devices on a surface in analogy to natural motors which operate at interfaces can expand their applicability. This has triggered intense scientific interest in the last decades.H‐pyrazol‐1‐yl)pyridine‐4‐carboxylic acid) on Ag(111). The bpp‐COOH molecules were too mobile to image by STM investigations performed at 200 K and above, following deposition at room temperature (RT). However, annealing at 373 K stabilised a complex arrangement which could be imaged at RT  lattice, corresponding to a hexagonal overlayer twisted anticlockwise by 14° with respect to the substrate lattice.Our investigation was initiated by the discovery of an intriguing self‐assembly upon depositing bpp‐COOH .− molecules  measurements. The most informative core‐level region is the O 1s region Figure , left. Tsyn,syn‐ or anti,anti‐configurations of the N atoms in adjacent pyridine–pyrazole units. As the anti–anti conformation is the most stable in the solid state,anti,anti‐structure is favoured by 1.86 eV per unit cell. A comparison of the hydrogen bonding schemes of the kagome syn,syn‐ and the anti,anti‐rotamers can rationalise a large energy difference between the two structures . In addition, the preferred orientation of the guest molecule matches the STM images only for the anti,anti‐configuration . The fcc hollow site was determined as energetically favoured for the pyridine of both anti,anti‐bpp‐COOH and bpp‐COO− (Supporting Information Table S2) and was used to position the molecular units forming the kagome structure on Ag(111). Importantly, theoretically simulated STM images, obtained from DFT calculations, also reproduce the relative contrast difference of the head group compared to the pyrazole side groups. The pyridine–carboxylic acid appears brighter than the pyridine–carboxylate, reaffirming the assignment of chemically modified bpp‐COO− tectons constituting the 2D kagome pattern on Ag(111) . However, the pyrazole orientation is not directly evident and similar contrast can arise from different planar rotamers  Figure .Subsequently, we analysed the orientation of the guest molecules in our “frozen” system Figure  by inspeCW‐ and ACW‐domains of the kagome network, which correspond to clockwise and anticlockwise rotations, respectively, of the kagome network with respect to the substrate lattice vectors /(ACW) guest. Figure ACW‐domains at 4 K. The CW‐ and ACW‐domains have opposite chiral induction effects on the guest molecule, resulting in different enantioselectivity . Importantly, the chiral induction is present even at RT, although the exact rotation angle of the guest has a broader distribution  between 0° and ±15°.Enantiospecific molecular interactions on solid surfaces may stem from chiral steps or kinkss Figure . Note thTo verify the origin of this chiral induction, we investigated the effect of the Ag(111) substrate. DFT energy optimisation of the supramolecular structure in the absence of the Ag substrate shows that the (CW)‐ and (ACW)‐bpp‐COOH guest orientations are energetically degenerate, both have a minimum at 0°; and in addition, reflection planes at 0° and 60° transform the energy landscape of the (CW) into that of the (ACW). Similarly, on the bare achiral Ag(111) surface (with no kagome network present), the rotational energy landscapes of the (CW) and (ACW) have energetically degenerate minima; these however occur at different orientation angles for the two surface enantiomers and away from 0°. Accordingly, the reflection planes now occur at different angles. This means that the degeneracy of the minima of the (CW) and (ACW) enantiomers is broken when one adds the effect of both the substrate and the kagome network . Consequently, it can be inferred that it is the non‐zero twist angle between the kagome network and the Ag(111) which breaks the symmetry between (CW) and (ACW) and is thus responsible for the guest chiral induction.The most frequently observed orientation of guest to host molecule matches well with the DFT‐optimised guest geometry. Having observed the switching of the position of the molecule in consecutive STM images at RT . However, the possibility of tip‐induced activated rotation under different tunnelling conditions exists. No correlation of the rotations and positions of the neighbouring caged guests was noticed, we therefore considered them as independent rotors. We recorded the frequency of rotation events by ≈120° as a function of temperature  further supports the observation of chiral induction.We also show that the charge transfer between the guest molecule and the host (comprising the kagome network and the Ag surface) correlates well with the height of the rotational barrier: the charge transfer is greatest at the minimum of the rotational energy landscape, and least for the most unfavourable guest orientation at 60° . Comparison with the confinement of an (ACW)‐bpp‐COOH guest in an − guests. Consideration of bpp‐COO− guests by DFT found indeed a significantly reduced barrier of 0.11 eV for rotation of such guest molecules. However, the bpp‐COOH guest is significantly favoured by 0.81 eV/unit cell , further reinforcing our interpretation.Interestingly, by scrutinising the optimised DFT geometries, the adaptability of the host with respect to the guest dynamic position in the optimised geometries becomes evident  substrate induces enantioselective organisation of the guest molecule inside the pores of the kagome network. The rotation of the guest molecule inside the pore is controlled by the kagome network: the chemical structure of the pore wall provides flappers that pin the guest molecule and prevent its unhindered rotation. The spontaneous formation of the host–guest assembly reported in this study is a model system for the investigation of delicate, dynamic, and enantiospecific interactions in confined spaces, which could help design enantioselective heterogeneous catalysts. We further anticipate that such ordered large‐scale networks with embedded individual switching units could be promising components for developing molecular nanodevices.We report on the spontaneous self‐assembly of bpp‐COOThe authors declare no conflict of interest.As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re‐organized for online delivery, but are not copy‐edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.Supporting InformationClick here for additional data file.