In a biological competition model, increasing one population reduces the growth of another. A two-species example is $\dot{u}=ru(1-u-v)$, $\dot{v}=v(1-\beta u)$, with both cross-effects negative. This asymmetric example has self-limitation only in $u$; disappearance of $u$ therefore permits unbounded growth of $v$. For $\beta >1$ its positive coexistence equilibrium is a saddle whose stable manifold separates exclusion outcomes.

The system $\dot{u}=u(1-u)-auv/(u+d)$, $\dot{v}=bv(1-v/u)$ combines logistic prey growth, saturating predation and a predator carrying level proportional to prey density. Its unique positive equilibrium is $u=v=s$, where $(1-s)(s+d)=as$. Its Jacobian matrix has determinant $bs\sqrt{(1-a-d{)}^2+4d}/(s+d)>0$ and trace $s(1-d-2s)/(s+d)-b$. The positive trapping construction for the Leslie-Gower model gives a compact positive region and a limit cycle whenever this equilibrium is a repeller.

The mass fraction multiplied by 100%.

An epithelioid macrophage is an activated macrophage with an enlarged, epithelial-like appearance. Such macrophages can form tightly organized groups in a granuloma, a tissue response that contains persistent material or infection. The resemblance concerns cell shape and arrangement: it does not make the cell an epithelial cell. Some epithelioid macrophages participate in the formation of multinucleated giant cells. ^[ref]

A machine instruction that reads a value from computer memory into a processor register. A demand cache miss may delay its result; a software prefetch has no such architectural result.

A machine instruction that writes data to computer memory. A store buffer can separate local completion from visibility to other CPU cores.

An instruction changes architectural state only if a specified predicate holds. With register renaming, a false conditional write must preserve the preceding logical destination value and satisfy younger consumers of that version.

Lymph is fluid within lymphatic vessels, derived from tissue fluid entering lymphatic pathways. Its composition depends on the drainage territory and current physiological conditions. Intestinal lipid-rich chyle is one specialized example, illustrating why all lymph should not be assigned one fixed composition.

A lymph node is an encapsulated lymphoid structure positioned along lymphatic drainage routes. Lymph enters through afferent pathways and passes through organized regions containing immune cells. This combines material sampling with cell interactions rather than acting as a purely mechanical sieve.

A lymphoid organ organizes immune-cell development or immune responses. Primary and secondary lymphoid structures have different roles; the spleen and lymph nodes are secondary examples. Having many lymphocytes does not make all such structures functionally interchangeable.

The spleen is an abdominal lymphoid organ that monitors and filters blood. Its splenic white pulp supports immune responses, while other regions remove or process circulating cells. It differs from a lymph node, which principally samples lymph arriving through lymphatic routes.

A central lymphatic capillary within an intestinal villus, receiving chylomicrons from intestinal absorption.

The main lymphatic channel delivering intestinal chyle and other lymph to the left jugulosubclavian region.

A lymphatic vessel transports lymph away from tissue spaces toward larger collecting channels. Its wall and valves support net forward movement. Skeletal movement, breathing and intrinsic vessel contraction can contribute rather than one central pump providing every driving force.

Lymphatic drainage moves tissue fluid and its contents into and through lymphatic vessels toward venous return. Valves and pressure changes support directional transport. Drainage can therefore fail through altered entry, obstruction or impaired propulsion, which are different mechanisms.

Pulmonary hypoplasia is insufficient development of the lungs, leaving too little functional pulmonary tissue for the demands after birth. It describes a developmental outcome rather than one unique cause.

Reduced space for lung growth, altered fluid conditions or impaired developmental signaling can reach that outcome through different routes. The distinction between small immature lungs and inadequate inflation of normally developed tissue follows from separating lung development from the mechanics of later breathing.

An alveolus is a small pulmonary air space whose thin wall participates in gas exchange with adjacent capillaries. Type I alveolar cells provide much of the exchange surface, while type II alveolar cells supply surfactant and other functions. Effective exchange requires both air access and blood flow.

A bronchus is a conducting airway branching from the trachea toward the lung. Larger bronchi have cartilaginous support and subdivide into smaller branches. Their conducting role differs from gas exchange across the alveolar surface.

Pulmonary surfactant is a lipid-and-protein material at the air-liquid interface of alveoli. It reduces surface tension and helps stabilize inflation. Production by type II alveolar cells links lung development and cellular secretion to the mechanical cost of breathing.

Loss of aeration as alveoli fill with material such as an inflammatory exudate.