Although we have an intuitive understanding of the behavior and functions of groundwater in the Earth's critical zone at the scales of a column (atmosphere‐plant‐soil‐bedrock), along a toposequence ...(ridge to valley), and across a small catchment (up to third‐order streams), this paper attempts to assess the relevance of groundwater to understanding large‐scale patterns and processes such as represented in global climate and Earth system models. Through observation syntheses and conceptual models, evidence are presented that groundwater influence is globally prevalent, it forms an environmental gradient not fully captured by the climate, and it can profoundly shape critical zone evolution at continental to global scales. Four examples are used to illustrate these ideas: (1) groundwater as a water source for plants in rainless periods, (2) water table depth as a driver of plant rooting depth, (3) the accessibility of groundwater as an ecological niche separator, and (4) groundwater as the lower boundary of land drainage and a global driver of wetlands. The implications to understanding past and future global environmental change are briefly discussed, as well as critical discipline, scale, and data gaps that must be bridged in order for us to translate what we learn in the field at column, hillslope and catchment scales, to what we must predict at regional, continental, and global scales.
Key Points:
Groundwater is relevant to large‐scale patterns of dynamics in land ecosystems
More observations and syntheses are needed to illuminate the opaque subsurface
Basic groundwater processes need to be represented in earth system models
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This paper develops a structural model of newspaper markets to analyze the effects of ownership consolidation, taking into account not only firms' price adjustments but also the adjustments in ...newspaper characteristics. A new dataset on newspaper prices and characteristics is used to estimate the model. The paper then simulates the effect of a merger in the Minneapolis newspaper market and studies how welfare effects of mergers vary with market characteristics. It finds that ignoring adjustments of product characteristics causes substantial differences in estimated effects of mergers.
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BFBNIB, CEKLJ, INZLJ, IZUM, KILJ, NMLJ, NUK, ODKLJ, PILJ, PNG, SAZU, UL, UM, UPUK, ZRSKP
Vegetation modulates Earth's water, energy and carbon cycles. How its functions might change in the future largely depends on how it copes with droughts
. There is evidence that, in places and times ...of drought, vegetation shifts water uptake to deeper soil
and rock
moisture as well as groundwater
. Here we differentiate and assess plant use of four types of water sources: precipitation in the current month (source 1), past precipitation stored in deeper unsaturated soils and/or rocks (source 2), past precipitation stored in groundwater (source 3, locally recharged) and groundwater from precipitation fallen on uplands via river-groundwater convergence toward lowlands (source 4, remotely recharged). We examine global and seasonal patterns and drivers in plant uptake of the four sources using inverse modelling and isotope-based estimates. We find that (1), globally and annually, 70% of plant transpiration relies on source 1, 18% relies on source 2, only 1% relies on source 3 and 10% relies on source 4; (2) regionally and seasonally, source 1 is only 19% in semi-arid, 32% in Mediterranean and 17% in winter-dry tropics in the driest months; and (3) at landscape scales, source 2, taken up by deep roots in the deep vadose zone, is critical in uplands in dry months, but source 4 is up to 47% in valleys where riparian forests and desert oases are found. Because the four sources originate from different places and times, move at different spatiotemporal scales and respond with different sensitivity to climate and anthropogenic forces, understanding the space and time origins of plant water sources can inform ecosystem management and Earth system models on the critical hydrological pathways linking precipitation to vegetation.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
We present a general procedure for constructing exact black hole solutions with electric or magnetic charges in general relativity coupled to a nonlinear electrodynamics. We obtain a variety of ...two-parameter family spherically symmetric black hole solutions. In particular, the singularity at the center of the space-time can be canceled in the parameter space and the black hole solutions become regular everywhere in space-time. We study the global properties of the solutions and derive the first law of thermodynamics. We also generalize the procedure to include a cosmological constant and construct regular black hole solutions that are asymptotic to anti–de Sitter space-time.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
A
bstract
The physical relevance of the thermodynamic volumes of AdS black holes to the gravity duals of quantum complexity was recently argued by Couch et al. In this paper, by generalizing the ...Wald-Iyer formalism, we derive a geometric expression for the thermodynamic volume and relate its product with the thermodynamic pressure to the non-derivative part of the gravitational action evaluated on the Wheeler-DeWitt patch. We propose that this action provides an alternative gravity dual of the quantum complexity of the boundary theory. We refer this to “complexity=action 2.0” (CA-2) duality. It is significantly different from the original “complexity=action” (CA) duality as well as the “complexity=volume 2.0” (CV-2) duality proposed by Couch et al. The latter postulates that the complexity is dual to the spacetime volume of the Wheeler-DeWitt patch. To distinguish our new conjecture from the various dualities in literature, we study a number of black holes in Einstein-Maxwell-Dilation theories. We find that for all these black holes, the CA duality generally does not respect the Lloyd bound whereas the CV-2 duality always does. For the CA-2 duality, although in many cases it is consistent with the Lloyd bound, we also find a counter example for which it violates the bound as well.
In General Relativity, addressing coupling to a non-linear electromagnetic field, together with a negative cosmological constant, we obtain the general static spherical symmetric black hole solution ...with magnetic charges, which is asymptotic to anti-de Sitter (AdS) space-times. In particular, for a degenerate case the solution becomes a Hayward–AdS black hole, which is regular everywhere in the full space-time. The existence of such a regular black hole solution preserves the weak energy condition, while the strong energy condition is violated. We then derive the first law and the Smarr formula of the black hole solution. We further discuss its thermodynamic properties and study the critical phenomena in the extended phase space where the cosmological constant is treated as a thermodynamic variable as well as the parameter associated with the non-linear electrodynamics. We obtain many interesting results such as: the Maxwell equal area law in the
P
-
V
(or
S
-
T
) diagram is violated and consequently the critical point
(
T
∗
,
P
∗
)
of the first order small–large black hole transition does not coincide with the inflection point (
T
c
,
P
c
) of the isotherms; the Clapeyron equation describing the coexistence curve of the Van der Waals (vdW) fluid is no longer valid; the heat capacity at constant pressure is finite at the critical point; the various exponents near the critical point are also different from those of the vdW fluid.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Catchments, generally understood as the drainage areas of low‐order streams, are often regarded as closed hydrologic entities; that is, precipitation (P) minus evapotranspiration (ET) over a ...catchment equates stream outflow (Q
r). Here, we review evidence that catchments can be leaky due to groundwater outflow or inflow across topographic divides, based on catchment mass balance across a continent and several site‐based studies across the globe. It appears that a catchment is more likely to be leaky with the combination of the following factors: small catchment size, positioned at either the high or low end of a steep regional topographic and climatic gradient, underlain by deep permeable substrates that extend beyond the study catchment, and in drier climate or dry seasons and droughts. Catchment leakage has hydrological, geochemical, and ecological implications. Thus, catchments are best framed as semiclosed hydrologic units perched on top of a larger, regional hydrogeological system with no real boundaries regarding the movement of water and solutes.
This article is categorized under:
Science of Water > Hydrological Processes
Water and Life > Nature of Freshwater Ecosystems
Catchments are leaky units perched on a larger, regional hydrogeological system.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Synthetically directing T‐cells against tumors emerges as a promising strategy in immunotherapy, while it remains challenging to smartly engage T cells with tunable immune response. Herein, we report ...an intelligent molecular platform to engineer T‐cell recognition for selective activation to potently kill cancer cells. To this end, we fabricated a hybrid conjugate that uses a click‐type DNA–protein conjugation to equip the T cell‐engaging antibody with two distinct programmable DNA nanoassemblies. By integrating multiple aptameric antigen‐recognitions within a dynamic DNA circuit, we achieved combinatorial recognition of triple‐antigens on cancer cells for selective T‐cell activation after high‐order logic operation. Moreover, by coupling a DNA nanostructure, we precisely defined the valence of the antigen‐binding aptamers to tune avidity, realizing effective tumor elimination in vitro and in vivo. Together, we present a versatile and programmable strategy for synthetic immunotherapy.
A chimeric antibody‐nucleic acid T‐cell engager (CAN‐TE) redirecting T cells to precisely target and potently kill the cancer cells by coupling 1) a dynamic DNA circuit with high‐order logic function for smart cell recognition or 2) a multivalent aptameric DNA nanostructure to control the targeting avidity for tunable immune response is reported.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We study the contributions for the
K
+
K
-
and
K
0
K
¯
0
originating from the intermediate states
ϕ
(
1020
)
and
ϕ
(
1680
)
in the charmless three-body decays
B
→
K
K
¯
h
, with
h
=
(
π
,
K
)
, in ...the perturbative QCD approach. The subprocesses
ϕ
(
1020
,
1680
)
→
K
K
¯
are introduced into the distribution amplitudes of
K
K
¯
system via the kaon electromagnetic form factors with the coefficients taken from the fitted results. The predictions of the branching fractions for the decays
B
→
ϕ
(
1680
)
h
with the intermediate state
ϕ
(
1680
)
decays into
K
+
K
-
or
K
0
K
¯
0
are about
6
-
8
%
of the corresponding results for the quasi-two-body decays
B
→
ϕ
(
1020
)
h
→
K
+
K
-
h
in this work.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A
bstract
We study upper bounds on the growth of operator entropy
S
K
in operator growth. Using uncertainty relation, we first prove a dispersion bound on the growth rate
|∂
t
S
K
| ≤
2
b
1
∆
S
K
, ...where
b
1
is the first Lanczos coefficient and ∆
S
K
is the variance of
S
K
. However, for irreversible process, this bound generally turns out to be too loose at long times. We further find a tighter bound in the long time limit using a universal logarithmic relation between Krylov complexity and operator entropy. The new bound describes the long time behavior of operator entropy very well for physically interesting cases, such as chaotic systems and integrable models.
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